6.5 Light machinegun

In another thread in this forum, I could see that there is no link currently developed for 6.5 Grendel ammunition. I may be controversial, but I dont see the great need for a beltfed infantry-machinegun. Beltfeds are heavy, complicated to operate, and last but not least EXPENSIVE... Magazines are much easier and more pleasant to carry, and given that both the MG and rifle can use the same magazines, it is also a lot more practical.

The big issue is of course capacity. 30 rds doesnÇt sound like very much in a machinegun. That could easily be fixed. The problem with large-capacity magazines in orthodox bottomfeed machineguns or rifles, is that it is difficult to maintain a low prone position, because the magazine is touching the ground.

The answer is actually very easy: Top-feed, like the Bren-gun. Then you could have a 40rd magazine, and it would not be a problem at all. A top-feed is much easier to operate, because the co-gunner can change the magazine in less than two seconds. Also, having access to compatible 40 rd magazines would be very nice for the other members of the squad, especially in FIBUA.

To keep the weight down, one could get rid of the QCB, and in order to keep the volume of fire high, one should simply employ more light machineguns. Maybe as many as three per squad. Then it would be possible to keep machinegun-fire at the target continuously for much longer durations of time, than it is with the minimi. The reduced weight also means that the potential ammo-load can be substantially increased...

Because of the reduced weight of such a machinegun, it could even be light enough to use as an assaultrifle. With a sufficiently long barrel, it could even work as a "sniper-rifle" It should be in a role comparable to the RPK-lmg in Russia, but much better.

I believe the ideal companion for 6.5 Grendel would be beltfed medium/heavy machineguns in .338 Lapua magnum. These should not be used by normal infantry, but rather being used on tripods in fire-bases, providing covering-fire for infantry.

Having served as a machinegunner during my military training in the northern parts of Norway, and having served in SFOR and KFOR, also as a machinegunner, I should have my share of experience with machinegun-belts in demanding conditions...

Why would top feed be preferable to a sten style "side feed"? Not only does it keep your mag from sticking up like a sore thumb, but it puts it in front of your face, helping to shield your face from kicked up dirt and debries, and allows you to moniter your ammo supply more reddily.

Balance is the key-word. It would be difficult to fire accurately, because the horizontal CG would be moving as you are firing, not to mention you would have to counterbalance it.

In the topfeed configuration the magazine is out of the way, and the gunner is able to stay lower. The magazine sticking up may look a bit stupid, "but if it works it aint stupid". Just ask some who has actually handled the Bren-gun. It was actually used in GulfWar 1 by the brits, because the LSW was unsufficient, and jammed frequently. A lot of soldiers in the British forces still wishes for the return of the Bren-gun, because it was extremely accurate and reilable.

BTW, it is mainly your co-gunners job to monitor the ammo.

Cool and I have discussed the Bren fed approach on many occasions and we are both fans, although he perhaps less so than I. When you fleshed out the operational issues of crew coordination the case became even more compelling. One idea we had wondered about that you could throw light on is that of a stagger-clip feed ala the Berretta M2 15 shot clip. I hadn't thought of the CG issue, but since the weight of the lower receiver is offset in whole or in part by the weight of the clip I can immediately see how that would make for a more accurate weapon.

I also think we are getting close to the day when a CCD back will be put behind most rifle scopes, at least the expensive NVG type to provide light amplification. Once this is done it is a short leap to put the front side of the scope ahead of the Bren clip and the back side (a 2x3 or so TTF screen) behind the clip. This also allows one to move the back of the sight using an optic fiber up to 100 meters or so, allowing the observer and gun to be in different places. This should offer some great advantages for surveillance and possibility of safely firing the tripodded weapon from the bottom of a trench. Come to think of it, the optic fiber could be branched so an observer and the gunner could both have use of the sight at the same time. This offers the possibility of one scope for a gunner and spotter.

As for the .338 MMG, I have liked this idea for some time now. My interest is in providing overmatch against other MMGs so a light recon vehicle (my PAV concept) can carry a large ammo compliment and still outrange a gun up to and perhaps including a 50BMG. (Using a VLD profile ala the LM-105 of Lutz Moeller) MGs with longer ranges would seem to offer many advantages, especially when able to replace traversal and search fires with simple traversal with what one would assume to be close to a 10:1 ammo and time savings with the expected increase in hit probability as targets have little time to find cover. Since you have the experience to comment I would very much like to hear your views on why you like the .338 MMG concept. My understanding is either a UK or SA firm is developing one.

Finally, I find the idea of a Gast-principal gun in the BRM-15x115 caliber range, perhaps a modified GSh-23 with sabot or necked down, very promising. They are reported to be very reliable, gas driven, two barrels, and a 3-4,000rpm rate of fire. I would favor a slower rate of fire, except where air-defense is concerned where the ROF would be very welcome. A thin sabot should dramatically reduce barrel wear while punching up the GSh-23's 800mps velocity to something more in the 1000-1200mps range, while the existing slow, heavy 23mm munitions would be great for MOUT operations.

Thanks! I have been thinking out this gun for some time now. And would love to be able to realize it one day...

As I«m a bit fed up by the weight and bulk of beltfeds, I tried to figure out how a machinegun can be as practical and handy as possible.

Beltfeeding was the first thing I gave up on. It makes the weapon heavy, complicated, and it exposes the interior to dust, snow and vegetation.

As ammodrums is not very reliable, they were not an option either.

Magazinefeeding is probably the best solution, and the Bren-gun has an excellent reputation for reliability.

Quick-change barrel is usually not needed, and does not increase the rate of fire dramatically. If a non-changeable barrel is heavy enough and has sufficient cooling-area, or perhaps even active cooling, like the russian "Pecheneg" (new PKM-mg), then a lot of weight can be saved, both in the QCB-mechanism, and the extra barrel itself.

Also the idea of a separate screen on electro-optical sights has struck my mind, or even a periscope type sight. The germans used it on tripodded MG-42s during 2WW, and are still using it on the MG-3.

The idea of using .338 for a medium/heavy machinegun is because it is comparable to 7.62 in weight and size, but has qualities comparable to 12.7 (50cal). And is thereby some kind of a "big-brother" to the 6.5 Grendel. It should even be possible to fire from a bipod, something the 12.7 hardly is, except if you add a very big muzzlebrake.

Unfortunately, I dont know very much about exotic gun-designs.

BTW, Im not familiar with "stagger-clip-feed"... Are you talking about magazines or clips that you insert into a magazine?

The Bren is a GREAT gun, however, generally U.S. MG's prefer belt feed. The M249 had a mag feed option--no one liked it, used it, or wanted it, so the Mk46 was made belt feed only. There is a large, well known European manufacturer that already has protoype .338 MMG's (belt fed of course)...

Actually I see the error of my earlier evaluation. My current project is actually inverting a mini-14/30 into a "bren style" bullpup, to be followed by developing a horizontal magazine similar to the P90, with the shells at an angle less than 90 degrees to the feed port. The design in mind would also eject out the bottom, ala P90 for true ambidexterity, and would allow the use of "saddle drums" and possibly a belt feed module actuated by the action (since the piston would be on top in an inverted Mini-14).

I dont see the great need for a beltfed infantry-machinegun... The answer is actually very easy: Top-feed, like the Bren-gun. Then you could have a 40rd magazine, and it would not be a problem at all.
Your argument has much merit, but does overlook one very substantial problem: the U.S. Army has a long-standing prejudice against top-loaders, despite their successful employment by the British Army and the Waffen SS. It would be a steep uphill battle to get such an LMG replacement adopted.

For those who might wish to try the top-magazine concept for themselves, Robinson Armament does advertise a Bren-type version of their M96 rifle. http://www.robarm.com/RA_m96_bren.htm
I believe the ideal companion for 6.5 Grendel would be beltfed medium/heavy machineguns in .338 Lapua magnum.
How about the .408 CheyTac? It appears to deliver significantly better performance than .338 Lapua, offering near-.50 caliber capability in a cartridge approx the same length and bulk as .338 LM.

Not only is that why I am trying to develop the AR equivalent to the P90, but also the interface for the belt feed based off a modual clipped into the same location as the magazine. In fact, if it works as planned and I can figure out an indexing system, I might be able to figure out a high capacity magazine that uses the reciprocating motion of the piston to index the next round, thereby increasing the capacity of the magazine by getting rid of the storage space for a compressed spring (used for holding tension in a normal magazine). I know, pipe dreams, but since I now have a rifle with the action I was looking at basing this off of in the beginning, I can start working on the idea a little more agressively.

Oh, and the overall concept would be a system that could do everything they expect from the XM8, but in a better balanced, american made, 6.5 Gren from the beginning package that could be as small as an enforcer style whippit or P90, up to a full LMG or sniper platform depending on the component systems.

Im familiar with the M-96 topfed. It is one of my sources of inspiration.

The M96 could very well be the solution, even though it«s based on the Stoner 63, which could be a problem (or not). However if Robinson Arms could make a new topfeed, based on the XCR, I believe it could be much better...

About American traditions, the foremost I believe is about the lowest bidder taking the cake... And the last magazine-fed machinegun in normal service was the BAR, which has achieved an almost iconic status.

To keep the weight and costs down, it would be very convenient to base the machinegun on an excisting assault-rifle, making minor adjustments to the design, to "ruggedize" it, and make it capable of firing large quantities of ammo in a relatively short duration of time.

The price of a M249 for the military, I believe, is about 6500$. For the same amount of money, it should be possible to buy three Bren-style machineguns, with heavy, fluted barrels. And in addition it should eliminate two assaultrifles in every squad, saving even more money, without compromizing in firepower or abilities.

The only downside compared to the M249 would be that it«s not able to shoot 1000 rds in one burst... In reality this never happens, unless faced with "human waves"...

Downwards-ejection is not very desirable, as hot brass could get inside your uniform, burning your arms. For a machinegun, ejection downwards to the left is the most desirable solution, as the best positioning of the co-gunner is on the right side. That way he stays out of the gunner«s field of view, and can be positioned closer to the gunner.

Part of the idea of basing the machinegun on an assaultrifle is that it would still have the size, weight and ergonomics of an assaultrifle, and could be used as an assualtrifle.

Because the .338 could be fired from 10 kg machineguns, while the CheyTac would require a few kgs extra, maybe approaching 16kgs. (highly theoretic numbers)

A Cheytac MG would be excellent in vehicles, but would be a bit too far on the heavy side for hauling around in difficult terrain to set up a fire-base with sufficient amounts of ammo. Also, the .338 is getting very popular amongst snipers.

It would be very interesting to know who the manufacturer of this .338 MG is. My instincts says FN, because as far as I know, HK has, to this date, not released one .338 gun.

The Bren is a GREAT gun, however, generally U.S. MG's prefer belt feed. The M249 had a mag feed option--no one liked it, used it, or wanted it, so the Mk46 was made belt feed only. There is a large, well known European manufacturer that already has protoype .338 MMG's (belt fed of course)...

The reason for nobody liking the mag-feed on the M249, is becase it literally EATS magazines, destroying them. It is also very unreliable when fed from magazines.

Im familiar with the M-96 topfed. The M96 could very well be the solution, even though it«s based on the Stoner 63, which could be a problem (or not).
I didn't mean to propose the M96 Bren as a "solution"...I was only suggesting it as a test bed for getting hands-on experience with a top-fed weapon that weighs considerably less than a .303/7.62 Bren gun. As a plus, it seems like the M96 Bren should be fairly easy to convert to 6.5 Grendel. (Would such a conversion be called a Brendel?) :D
Part of the idea of basing the machinegun on an assaultrifle is that it would still have the size, weight and ergonomics of an assaultrifle, and could be used as an assualtrifle.
The idea has some advantages, and is one reason why the Russkis switched from the belt-fed RPD light machine gun to the (AK-based) RPK automatic rifle. The US Army's XM8 family also was to have an automatic rifle replace the M249 LMG, although the leadership has apparently dropped that notion and now wants another LMG to supersede the M249.

The XM8 Light support weapon was in my eyes a bad idea. IMO it had a much too light barrel, with bad heat-excange. Also, large parts of that weapon was made of plastic, which is less than desirable in a machinegun, because they tend to get really hot.

By employing a heavy fluted barrel, the gun would have been able to withstand heat much better, as well as cooling down more efficiently.

Another problem with the XM8 light support weapon is that it is difficult for the co-gunner to assist in reloading the gun, as it is easier for the gunner to reload himself. With topfeed a seasoned co-gunner can change mags in one second.

In a theoretical duel between the M249 and a Bren-style, given that the Bren-style had the same rate of fire, where the goal was to shoot 200 rds in as short a time as possible. Where both guns started empty, The M249 employing 2x100rd-pouches, and the Bren employing 5x40rd-mags. Both gunners receivin assistance from a co-gunner.

Who would have won?

the Ares Shrike fits that bill. Its around the same weight as the AR15/M16/M4 depending on barrel lenght, it has a quick change barrel, and can use the belt feed or standard AR mags without eating the mags, and is supposedly reliable with both.

Thats IF its actually in production.

IMO, the Shrike sounds too good to be real.

It must have some problems, since it has not been put to production. It is probably dragging along a few of the flaws of the AR-family, like considerable fouling inside the mechanism, which is not good for reliability. And how is reliability in extreme cold, or dusty conditions? I actually do not believe it is rugged enough for the machinegun-role. But these are only assumptions from my side, and we will just have to wait and see...

In a theoretical duel between the M249 and a Bren-style, given that the Bren-style had the same rate of fire, where the goal was to shoot 200 rds in as short a time as possible. Where both guns started empty, The M249 employing 2x100rd-pouches, and the Bren employing 5x40rd-mags. Both gunners receivin assistance from a co-gunner.

Who would have won?
I can't say for certain how such a duel would settle out, but it may be a somewhat irrelevant contest, anyway. I'm pretty sure that in the US Army the SAW gunner does not have an assistant, or co-gunner, so a valid comparison would have to be done just with individual, unassisted gunners.

Does the Norwegian Army provide SAW gunners with co-gunners?

Actually the Shrike uses a side mounted piston action instead of the gas tube so it shouldn't foul anywhere near as bad as an AR. My only guess would be overheating because of less metal in the reciever to act as a heat sink. I would be nice if they were more forthcoming with any problems.

IF it works as advertized, you actually have a SAW that you would WANT to mount an M203, LSS or some other add on system, just to add weight and make it a little more controllable.

I can't say for certain how such a duel would settle out, but it may be a somewhat irrelevant contest, anyway. I'm pretty sure that in the US Army the SAW gunner does not have an assistant, or co-gunner, so a valid comparison would have to be done just with individual, unassisted gunners.

Does the Norwegian Army provide SAW gunners with co-gunners?

As the Norwegian Army still employs the MG-3 in the SAW-role, we use a co-gunner.

Still, without co-gunner, I believe the magazine-fed would give the M249 very strong competition.

Anyway, this duel is not irrelevant, because it shows the ability of a weapon to provide suppressive fire without long breaks.

As I have never fired the M249, how long does it take to change the ammo-box, insert a new belt and resume firing? I would assume 10-15 seconds... Unassisted... With the MG-3, we were down to 2-4 seconds, without an ammo-box, but with a co-gunner. Without a co-gunner, but with new belts ready, I would have needed 6-10 seconds.

I would still like to have a co-gunner, no matter what machinegun... As it is good to have somebody to carry ammunition, observe in the target, and take over the machinegun if the gunner should be hurt. Then the "teamleader" could apply first-aid, while someone still put rounds on the target.

Actually the Shrike uses a side mounted piston action instead of the gas tube so it shouldn't foul anywhere near as bad as an AR. My only guess would be overheating because of less metal in the reciever to act as a heat sink. I would be nice if they were more forthcoming with any problems.

IF it works as advertized, you actually have a SAW that you would WANT to mount an M203, LSS or some other add on system, just to add weight and make it a little more controllable.

It could very well have something to do with the aluminium in the receiver not being tough enough to withstand abuse when being very hot...

If it is so light they have to add an UGL to make it controllable, then I would much rather have added a very heavy, fluted barrel, working as a heatsink, removing the need for a QCB.

In my opinion UGLs are too cumbersome to have under a rifle (Im used to the G3 rifle with HK79 UGL). At least in the 40mm calibre which is used to day. Making them in 30mm calibres would have been much better. And also increasing the length of the round, to maintain lethality and range compared to the 40mm.

(...)

BTW, it is mainly your co-gunners job to monitor the ammo.I believe that most expeditionary-type military forces would like to rid themselves of co-gunners to the extent possible (in other words, for SAWs and GPMGs, probably not for HMGs).

That will not prove easy... But why? A co-gunner enhances the capabilities of a machinegun. If he doesnt have to mess around with belts and spare-barrels, he would have a far easier job.

Also, if the squad is consisted of 3 man MG-teams (gunner, co-gunner and teamleader/squadleader), the teamleader can also work as a co-gunner when the co-gunner is out of MG-ammo (every soldier should be able to do the job of the soldier directly above or under him).

Still, without co-gunner, I believe the magazine-fed would give the M249 very strong competition.
Concur. And it's conceivable that, in some conditions, it could even be better than the M249. Hmm...this just caused me to recall an article that you might find of interest:
http://www.mca-marines.org/Gazette/2004/04eby1.html
Anyway, this duel is not irrelevant, because it shows the ability of a weapon to provide suppressive fire without long breaks.
I didn't mean that it was totally irrelevant, only that comparing the two guns with use of co-gunners is not applicable to the way that the US Army employs a squad auto. However, if the Norwegian Army would use co-gunners with a SAW, then such a test would be very relevant for them.
As I have never fired the M249, how long does it take to change the ammo-box, insert a new belt and resume firing? With the MG-3, we were down to 2-4 seconds, without an ammo-box, but with a co-gunner. Without a co-gunner, but with new belts ready, I would have needed 6-10 seconds.
My experience is with the M60, but it was so long ago that I don't now remember how long it took to reload. But, since the feed mechanism and reloading procedure is, I think, essentially the same for MG3, M60, and M249, I'd expect reloading times to also be virtually the same.
I would still like to have a co-gunner, no matter what machinegun...
I understand, and agree that it would have the advantages you've noted. However, that is a decision that is/will be made by those in charge of determining what doctrine will be used.

Thanks for the extremely interesting link Stanc!

In my opinion, in terms of firepower, one beltfed is much better than one magazinefed machinegun.
But two magazinefeds is better than one beltfed, and three magazinefeds are somewhat equal to two beltfeds. The real difference is in terms of weight.

Theoretically, a 9 man squad (I am not aware of anyone using a 9 man squad, but that should free up 4 marines for other weapon-systems), equipped with two beltfeds, and a standard load of ammunition, should be heavier than the same squad equipped with three magazinefed machineguns, and the same load of ammo. Which again enables the squad to carry more ammunition, or additional protection or equipment.

I am not aware of anyone using a 9 man squad...
US Army mechanized and parachute infantry have 9-man squads, with one squad leader and two 4-man teams per squad. Each team has one SAW gunner, one grenadier, and two riflemen. (There's been ongoing debate about reverting to 11-man squads.)

HI
How about a Ameli 5.56 LMG in 6.5G.
The Ameli is a belt fed LMG made in spain- it looks a lot like a small MG42.

970mm length (38.2 inches)
400mm barrel (16 inch)
5.2 kg (11.5 lbs)
cyclic of 900 RPM
875 m/s (2870 ft/sec)

Compare the M249
1040mm (40.9 i)
520mm (20.6)
6.9kg (15.1lbs)
cyclic 750 RPM
915m/s (3000 fps)


add a couple of inches to the Ameli barrel to get a bit more velocity and a rail for optics/NVS in.
What velocity is a 19 inch overwatch getting- it won't be far behind that.
The Ameli is light, simple delayed blow back can operate from magazine or link has planty of room to fit a can on the front of the barrel if required
(don't know why you would need/want to fit a can to a lmg but on this one it's possible)
Quick change barrel, can be fitted with a burst/FA trigger group, intergrated bi-pod and can be mounted on a T&A tripod if required.
The weight you save can go into extra ammo.
Can be operated by one squad member- thus freeing the co-gunner to be used for either another LMG or ??

Could mean you now have 4 LMG's per squad.

Just an idea
later
P

Why would you want to fit a can on the end of a SAW? Because suppressors don't make you silent, they make you invisable. Not to mention that with the new breed of suppressor, you can handle full auto for sustainted periods without losing your suppression.
God that would be scary. Hearing the ripping fabric of incoming, but have nothing but impacts and the sonic crack of the bullets to figure out where its coming from. Water cool the sucker and it even masks your IR signature.

Imagine a sniper with a machinegun, and thermal sheilding for himself and his gun, piped into a heat sink down out of the line of sight. You'd have one scary bastard pinning you down while his buddies cut you off and either kill you or take you prisoner. Yikes

HI
I didn't realise can technology had come far enough to enable sustained FAS fire.
We haven't been able to have cans of any type for years and years so looks like I'm knind of behind the times.

later
p

HI
How about a Ameli 5.56 LMG in 6.5G.
The Ameli is a belt fed LMG made in spain- it looks a lot like a small MG42.

970mm length (38.2 inches)
400mm barrel (16 inch)
5.2 kg (11.5 lbs)
cyclic of 900 RPM
875 m/s (2870 ft/sec)

Compare the M249
1040mm (40.9 i)
520mm (20.6)
6.9kg (15.1lbs)
cyclic 750 RPM
915m/s (3000 fps)


add a couple of inches to the Ameli barrel to get a bit more velocity and a rail for optics/NVS in.
What velocity is a 19 inch overwatch getting- it won't be far behind that.
The Ameli is light, simple delayed blow back can operate from magazine or link has planty of room to fit a can on the front of the barrel if required
(don't know why you would need/want to fit a can to a lmg but on this one it's possible)
Quick change barrel, can be fitted with a burst/FA trigger group, intergrated bi-pod and can be mounted on a T&A tripod if required.
The weight you save can go into extra ammo.
Can be operated by one squad member- thus freeing the co-gunner to be used for either another LMG or ??

Could mean you now have 4 LMG's per squad.

Just an idea
later
P

The Ameli is rumored to not be very reliable.

Also I doubt that it is able to be mag-fed. The light weight (for a beltfed) also tells me that the barrel is too light for a machinegun. If I wanted to combine both belt- and mag-feed, I would rather have opted for the Israeli Negev...

The main reasons reason for me wanting to get rid of beltfeds in the SAW-role is that their relative complexity compared to magfeds make them less reliable in difficult conditions, and heavier than they need to be. Also a beltfed is more difficult and time-consuming to operate than a magfed, even without a co-gunner.

A can tends to reduce the speed of a round, and get extremely hot when used with automatic fire. An alternative could be the Krinkov flash-hider...
As bullets is not the only thing being able to suppress the enemy, but also sound...

Why would you want to fit a can on the end of a SAW? Because suppressors don't make you silent, they make you invisable. Not to mention that with the new breed of suppressor, you can handle full auto for sustainted periods without losing your suppression.
God that would be scary. Hearing the ripping fabric of incoming, but have nothing but impacts and the sonic crack of the bullets to figure out where its coming from. Water cool the sucker and it even masks your IR signature.

Imagine a sniper with a machinegun, and thermal sheilding for himself and his gun, piped into a heat sink down out of the line of sight. You'd have one scary bastard pinning you down while his buddies cut you off and either kill you or take you prisoner. Yikes

Actually, a water-cooling system would be great for a machinegun on a tripod... If you have a machinegun with a normal QCB-barrel, it should not be very difficult to make a barrel with liquid-cooling, to plug into a heat-excanger with a pump... Technology and warfare have gone a long way since WW1, as there would not be the need for day-long suppressing fire any more, which means the heat excanger could be as light as 3 or 4 kgs,. More than enough for modern-day suppressing fire...

As tracers is used for most machinegun ammo, the enemy would usually be able to figure out your approximate location, so the most important thing would be to hide your muzzle-flash... The source of the sound is not very easily located...

I think the state-of-the-art Ti supressors will withstand some level of automatic fire, and could be made to withstand almost constant auto fire if they were rib-vented.

Any thoughts on cooling barrels with hydraulic fluid - assuming you had a vehicle with a good hydraulic system - like the AAAV/EFV? (or a PAV)

Rib vents alone will increase heat dissipation about 3-5 fold depending on the rib design. The ribs should be interrupted (cut through the ribs), non-homogeneous in size, and thermally welded to the barrel. Adding a fan to this will increase heat dissipation up to 30x (I have this research somewhere. It is based on dissipating heat from a large electronic component. The heat gradiant is MUCH more favorable with a gun so these are conservative estimates.) One of my ideas was to create an MG-42 style barrel with bottle-neck fins that move back and forth in a loosely matching barrel cover so that the barrel's movement pumps air thru the fins. Concerned about barrel warping I switched to a radially cut set of "snake" flutes that engaged ball-shaped palls in an aluminum axial fan with a ratchet feature so the back and forth movement of the barrel powers an axial fan.

The discussion of the utility of a co-gunner adds to my conviction that a semi side-by-side seating arrangement (somewhat like an E6B Prowler) is the correct one for the PAV as is the overhead gun mount to keep the lap and "dash" area unencoumbered so ammo or maps or grenades or even belts can be passed back and forth in support of tight crew coordination.

The .338 seems like a nice step up in power as it was designed to penetrate 3 layers of body armor at 1000 yards and has close to 50BMG range. The .408 is an impressive technology but seems too close to the 50 to warrent another gun system. For anti-personnel the .338 seems about as heavy as there are good requirements to fill in that role. The CheyTac is substantially larger and heavier and is inferior to the .50BMG in anti-materiel. I do think it is an excellent sniper weapon, but question how many snipers can make use of the added capabilites the .408 offers over the .338.

For a new more powerful replacement for the .50BMG something is needed to defeat new armor systems on light vehicles that is somewhere between the M2 and 25mm Bushmaster. The 15.5x115 BRM FNL abandoned should be reevaluated. As stated I think the GSk-23 type dual barreled Gast action would be a good choice if the ROF could be slowed to the 1,200-1,800 range. This would be a vehicle mounted weapon only - due to weight and recoil. In 30mm, it is standard equipment on Russian attack helicopters and would make a great air-defense gun on a light vehicle with the full 3-5,000 ROF- or in street-sweeper role. As a gas action, it should be possible to slow the action down to some degree.

The general idea is to up-gun from 5.56 to 6.5, 7.62x51 to .338, and 50BMG to 15.5x115 in response to better body and vehicle armor, and of course, the desire when using light recon vehciles like the PAV to fight from standoff distances where kinetic weapons are easier to armor against and advantages in stealth and vision equipment are more dominant.

The stagger clip idea was to increase the Bren gun mag capacity by making the mag thicker to support a staggered load rather than taller. It should make for a stronger seat in the mag well too.

Putting two of these ideas together, I wonder how much a Bren mag AR gun in .338 would weight? The difference between bi-pod and tri-pod weight is very sustantial, so minimizing that requirement alone would tip heavily in the .338's favor. (I have a feeling the M240 could adapt to a .338 as it is very strong, but its heavy!)

I think the state-of-the-art Ti supressors will withstand some level of automatic fire...
I concur. Years ago I was associated with a company that developed suppressors constructed with stainless steel, and also titanium. I recall some full-auto testing, where the cans got extremely hot, but still functioned as designed.
The .338 seems like a nice step up in power as it was designed to penetrate 3 layers of body armor at 1000 yards and has close to 50BMG range. The .408 is an impressive technology but seems too close to the 50 to warrent another gun system.
Perhaps so. I only suggested the .408 for possible new machine gun caliber, because it's midway between .30 and .50 cal.
I do think it is an excellent sniper weapon, but question how many snipers can make use of the added capabilites the .408 offers over the .338.
For snipers, I've long wondered if it might not be better to go with a smaller (6.5mm? 7mm?) bullet diameter, rather than bigger. It'd allow higher ballistic coefficient and sectional density (for flatter trajectory, increased penetration, etc) at far less recoil than .338 Lapua or .408 CheyTac.

im wondering why no one has mentioned the ultimax as a viable SAW. its drum is very reliable (though needs a tool to reload). it is light (12 lbs i think) has no recoil and also can use standard m16 mags without destroying them. also i've heard that the original c mag, as opposed to the beta cmag, is also very reliable. plus i've never heard anycomplaints about the commie drum mags being unreliable.

Good point...it also has a very well designed gas system and quick change barrel. Not to mention it can be shortened to M4 sized or be full saw sized. Only problem would be rechambering it and the mags for 6.5G ;)

http://www.mca-marines.org/Gazette/2004/04eby1.html

The ultimax was tested extensively... RTFT.. :D

Some other thoughts on this research....

Combatants don't always know what's best for them. The Colt was clearly better than the rest, and I have a feeling that would be true even if the "familiarity" bias was removed by using veteran machinegunners. Weight helps, but there still seems to be a blindness that the weight need not be a permanent part of the weapon.

This is the same basic principal that allows me to flood the 2" honeycomb structures on the PAV and add 3-5,000 lbs with a garden hose once the strategic airlift (or tactical for that matter) is completed. The use of indigenous materials for armor is best exemplified by the extensive use of sandbags. Would anyone suggest flying the sand 12,000 miles? Of course not! Using water to add weight, cooling, and secondarily, crew sustainment is such an obvious idea it is a constant surprise it is not widely used - if at all.

A well-finned water jacket around the barrel can be filled for action and drained for maneuver. A clever design would have an inner chamber against the barrel insulated from the much larger outer chamber and exploit the temperature difference to run a simple sterling engine pump where the weight of a radiator was acceptable.


The claim that there is no statistical difference between the SAW and other platforms is sheer idiocy. I happen to have studied statistics up through graduate econometrics (where we studied what happens when statistical assumptions are violated and remedial action available to compensate - IE: how to conduct real-world statistical studies) and worked my way through graduate classes as a research assistant doing statistical studies - this claim is outrageous and professionally offensive :mad:

Moving on....

Lutz Moeller's LM105 represents the state-of-the-art in .338 development imho. It is a banded 6.5 calibers VLD bullet with a BC of about .95 and carries enough energy downrange to actually inflict a lethal wound when it arrives. A slightly more blunt-nosed version of this solid copper bullet has taken big game at over a mile. http://home.snafu.de/l.moeller/Ballistik/A_Ballistic_Coefficient_Discussion_with_Lost_River.htm
This bullet has won the .338 shootout again for 2005 - about 4 in a row now. It is capable of matching or besting the .50BMG and is very, very close to the .408 CheyTac. McMillan makes a killer (semi-auto) sniper system for it and rumor is CheyTac is working on one.

Because VLD bullets have sharp points they are easily shed by highly oblique (angled) armor common on well designed vehicle armor which is frankly not much used on current armored vehicles except for the frontal armor. For body armor though, angled armor is nearly impossible to create and the VLD design is therefore a very good anti-personnel choice. (The Pinnacle DragonSkin is the first exception to this rule as the cookies are overlaid on each other to create a 15-20% angle) Heavy cored tungsten and 500 BNH steel bullets can be used to offset some of the shedding effect of angled armor, but in general blunter is better, although a hollow point may give a bullet the purchase on the angled surface needed to keep the bullet's center of mass aligned. (??? pure speculation here)

The .408 is about 65% of the weight of the .50BMG while the .338 is about 40% if I recall. I'm not against the .408 for sniping - especially in places like the mountain of Afghanistan or the vast open deserts of Iraq's AnBar province, but it seems like a bridge too far for a MMG.

An intriguing idea would be a GSk-23 type Gast gun in 6.5 Grendel. The Gast guns are very lightweight and have very high rates of fire which is why generations of MIG fighters used them. They are an old German design dating back to 1917 and have been used extensively in the East Bloc countries. They are always twin barreled - intrinsic to the design - and seem to have ROF between 2,500 and 5,000 rpm. My guess is one could build a great Gast-Grendel for the weight of an M240 that would be extremely reliable (one of the design's great features) and would have the range and ROF to own a street or defensive position. ( double the ROF of the MG-42 )

Using the low heat Grendel with banded bullets and progressive twist barrels this would be an awesome MOUT gun that could overpower almost any other MG within its range in a fire-support asset duel. (The primary target for any fire-support weapon is the enemy's fire-support. Therefore this should be considered as the primary criteria for any such weapon.) This ROF makes it a crew-served weapon, but here the lighter ammo weight of the Grendel really shines.

While we are not currently facing a foe with CAS, the Gast-Grendel (Gastdel ???) would make an excellent close-in air-defense weapon for a Hummer, M113, PAV, or StarShip. The latter's ability to provide mezzanine level MOUT defense and suppressive fire for blue CAS when rolling in for a strike would be devastating - used in groups to provide mutual supporting fires up to 3 stories high in MOUT and overhead suppressive fire to advancing troops in open field combat. Slat armor would be a must - of course - as any StarShip would be an RPG magnet in MOUT.

http://www.canadiantactical.ca/catalog.pdf page 4.

Supressor for full-auto belt-fed MG.


Also, http://home.snafu.de/l.moeller/Lapua%20Sniper%20Competition.htm

5" groups at 750 meters... the LM-105 is just the apex of ballistics imho. An exerpt below...

7th Lapua Sniper Competition 2005

The competition followed the tradition to place several shooting stages with different tasks. The competition was not physically hard since the main idea is to measure the ability to make good range estimation, ability to read the wind properly and of course to shoot good at long ranges. The competitors got also points from proper movement and camouflage. Ranges had to be measured with mil-dot or similar reticle, no laser devises were allowed.

The first stage was a "terrorist" neutralization task. The competitors were shown a picture of a target that would appear somewhere near a traffic sign within 5 minutes. The target would be at the traffic sign for 1 minute and disappear. The shooter had to estimate the range and pick up the right target out of 5 different targets and hit the target inside a 5 cm ring at the center of the target. The target popped up at approx. 150 meters. Many shooters did not either hit the target where they should or could not make the difference between the targets and thus did not hit the right target. A 338 LM long-range gun is not the right gun for this kind of job.

The second stage consisted of two targets at approx. 450 meters. The task was to estimate the range and wind and to shoot the targets so that the shots would depart within 5 seconds from both team members. A gap over 5 seconds between the shots would have meant 0 points. We had our shots go so simultaneously, that the electronic calculator didn't even registrate two shots. Both targets fell down.

The third stage consisted of 8 targets at ranges from approx. 350 - 750 meters. We had a range card that was made the evening before. But the targets were not shown until now. There was 25 minutes time to stalk 25 meters to the shooting position, shoot the targets (both shooters) and get back beginning point unseen from the target area. The LM-105 was enjoyable to shoot. Even with a slight wind from the left, there was no need for wind corrections more than 0.25 - 0.50 MOA at 700 meters. Although the fine gun a human error made me miss one target at 660 meters.

The last stage was quite easy. The targets were at approx. 450 meters and partly behind bushes. The competitor had plenty of time to estimate the range and to shoot the targets.

I must admit that the 338 LM with the LM-105 bullet makes a difference at long ranges. The targets were 45 cm wide metal targets that fell down when hit. The height of the targets wearied from 40 - 70 cm, thus the flat trajectory and minimum wind drift makes sense.

The trajectory corrections that I made

300 0.0 moa
400 2.5 moa
500 5.0 moa
550 6.5 moa
600 8.0 moa
650 9.5 moa
700 11.0 moa
750 12.5 moa

That would mean that a bc. near 0.930 would be quite right and the velocity approx. 905 m/s.

With regards,
Tom Marsti, Dienstag, 26. Juli 2005 08:04

http://guns.connect.fi/gow/highpow.html

Note that a good suppressor improves accuracy by controlling the rather random structure of the gas charge following the bullet to the barrel end which over-takes it and destabilizes it by exerting random pressure and vacuum when passing the bullet. Suppressors control and shape this charge so the transition of the bullet from a high-pressure environment to ambient air is smoothed in a controlled environment.

Note the section on Barrel Torque. This is the reason I greatly favor the use of progressive twist barrels where the torque gradient across the length of the barrel is uniform as the bullet is eased into the twist at a log-linear rate. This also allows a greater % of the energy to be used to accelerate the bullet forward, lowering throat pressures, temperatures and wear. For a more detailed discussion of engraving forces see http://www.dtic.mil/ndia/2004arms/session9/siewert.ppt

Progressive twist barrels are required when using banded bullets to keep from shearing the bands off, but there is an additional payoff - minimal engraving force friction and still faster departure from the throat to further reduce pressures. In summary, it takes 38% more pressure to move a NATO M80 7.62x51 out of the throat of the barrel than an identical bullet which is banded like the LM-105! In short, you can crunch the load until it crys and still not stress the barrel. This technology was used by FNL in its 15.5x115mm .50BMG replacement VHMG program to reduce barrel wear to acceptable levels so it is indeed a mainstream technology.


http://www.gem-tech.com/HALO.html ... full auto..

...until the lead in the bullet melts from the heat of the barrel :D

I«m no expert in gun-technology, but as far as I know, silencers tend to slow the bullets down. On a battlefield, I would not like my rounds to be slowed down, because that means less effect in the target.

About the Ultimax, I«m sure it is a great MG, but I fear the drum would be unreliable in arctic conditions, because of too many moving parts... Also, drums are cumbersome to carry, and I fear it would be easy to destroy the feed-lips, because the most practical carrying method is with the bottom towards the body... But in a fire-support-role, drums would be much more practical, because they are quicker to change than belts, and don‚t get the same beating as they would in a rifle-squad.

BTW: With with the "Brendel" :) in an AR (as that probably is a more correct description according to solidpoint«s link)-role, a rifle-squad could use the co-gunners in the co-gunner-role, until close enough to really get effect form his own rifle (100-200m). This way, the "pairs" would split up when a larger volume of fire is needed, instead of more accurate fire.

I«m no expert in gun-technology, but as far as I know, silencers tend to slow the bullets down. On a battlefield, I would not like my rounds to be slowed down, because that means less effect in the target.

This is incorrect. The suppressor itself does not reduce the velocity. In some tests, you may even find that velocity has increased slightly due to 'free-bore boost.' However, in certain intregrally suppressed firearms, such as the MP5SD and Sterling L34A1, the velocity of supersonic rounds is reduced to subsonic by modifications to the barrel. Numerous ports have been drilled into the barrel to bleed off the propellant gases. Thirty 2.5mm holes are found in the MP5SD's barrel, and the L34A1's barrel is ported 72 times.

The M249 had a mag feed option--no one liked it, used it, or wanted it, so the Mk46 was made belt feed only. (belt fed of course)...

The M249 still has a mag feed option & it is being used every day in Iraq & Afganistan. I liked it, I used it, & I wanted it, & every other saw-gunner I ever met did too. No one wants to use a 30 rd. mag untill they run out of 200 rd belts, then you can't get enough 30 rd mags. Its like an alcoholic that wants whiskey. He may say beer sucks, but when he runs out of whiskey he'll steal your beer if he has too & even filter aqua-velva through a piece of light bread & drink that. Theres very little more depressing than carring a empty Machine gun in combat. You want ammo worse than a crack-whore wants a fix.
Never seen or heard of a MK46, so it must be irelevant. When it becomes std-issue to the real army, then its relevant. If its just some expensive toy that Spec-ops is playing with, its nothing. You'd have to be an idiot not to want to be able to use the same mags everyone else in your squad uses. Geesh its a no-brainer dude. M9

M9,

Was it you that bid us farewell from the states and was destined for SWA? If so, how is it going? It sounds like we are taking off the gloves a bit in SWA, spill-over from Iraq I assume as the general level of nastiness tends to seek equilibrium.

Daniel,

Thank you for the additional info. It was my belief that suppressors added slightly to the velocity as the "rouge waves" of the chaotic pressure wave are prevented from overtaking the bullet by the various bulkheads in the baffles so only the forces pushing rather linearly on the base of the bullet are allowed to continue forward. The very dramatic side-effect seems to be in tight groups due to repeatability, but a secondary effect - it was my belief, now confirmed - was a slight improvement in velocity.

PS: It's really nice to take a few moments while letting my tired body heal up from the too scarce physical work and join the discussion again. A real pleasure - thanks again all! :)

M9,

Was it you that bid us farewell from the states and was destined for SWA? If so, how is it going? It sounds like we are taking off the gloves a bit in SWA, spill-over from Iraq I assume as the general level of nastiness tends to seek equilibrium.

:)

I went as far as Kuwait this time & am back in CONUS now. My unit was disbanded due to understrength & the personnel were used as fillers for other units. The slot they offered me would have been a reduction in rank & pay as well as being an MOS I have no experence or desire to aquire any in, as such I would have had to volunteer to fill it. I declined. I could retire as my time was up untill they instituted "stop loss" which extended my ETS untill 2031. I'll be pushing 80 years of age if I survive untill 2031. If we keep on our current course we will have an army of senior citizens riding into battle in their wheelchairs. Its a weird backward draft, the 20 year olds evade service & the old warriors that are past retirement are forced to stay, even though they've already done their part many times over in some instances. M9

... a new cost-cutting measure at the VA? Keep all of us old farts on the front lines until our luck runs out? I suppose recruiting from the Young Republicans is out of the question as they need to be around the munitions factory to pick up daddy's corporate welfare check. :mad:

M9

It was CWO4 who was bidding us farewell and heading off to SWA. I stumbled across the post by accident. Better lucky than good... :D


M9, I have a theory I was wondering if you would comment on. My theory is that a person's dental work is a fairly good indicator of their economic status in life. The reason is even a short period of neglect or lack of means will result in a degradation in apparent dental health. This has a useful corollary if true.

If you are on patrol in Iraq, manning your MaDuce, and that white Toyota truck is not slowing down, smile a great big toothy smile and watch the driver closely. Returning a smile is VERY, VERY deeply ingrained in the human psyche and they will likely grin back. If those teeth are nice and white and straight squeeze those triggers hard and don't lift the barrage until there is no piece of meat left big enough you couldn't buy it for less than ten bucks at a Manhattan butcher shop. The reason is simple. If under the Iraqi embargo this Sunni bastard has had the unbroken financial support of Saddam you can bet he intends you no good. If on the other hand, like Al Sadar, he and his have been persecuted for decades, their teeth will look like bad cheese, and there is a good chance this person needs a warning shot to make up for his lack of education.

So, am I right about this? Or is there something about the Iraqi theater that makes this test unreliable? I study the pictures coming back from Iraq very closely. If you look at the pics of the crowd pounding their fists in the air and firing off their AKs at the bridge in Fallujah… where they butchered those contractors... all perfect teeth. If you look at pictures of Muctada Al Sadar his teeth look like Roquefort cheese. Think about it.

I think you've got the right idea to think outside the box, but I don't know if your analysis holds in this instance.

Many poorer countries can't afford the sugary western delicacies that promote tooth decay, thus "poor" people on a "poor person's diet" of natural and healthy foods, might actually have better dental health than us "rich" Westerners!

John

P.S. I suppose I should qualify that by saying that if you've got "poor" people with no dental hygiene habits and with access to cheap sugary foods, then you've got a recipe for dental disaster.

John,

Those sugary foods actually are much less of a problem than we have been indoctrinated to think. This finding was published and got some very limited press about 3-4 years ago. Sugar brings on an instant saliva response, and saliva kills many of the bacteria that cause tooth decay. (In many poor countries they spend what little money they have on Coke, but it's not the problem) The real culprits are things like sticky rice and potatoes - especially the former.

In addition to the general level of tooth decay, it costs money to have straight teeth. It turns out that in a nasty twist of fate, many people inherit their mouth from one parent and their teeth from the other, so tooth and mouth size mismatches are very common. The RX is of course quite expensive. If Saddam isn't keeping you in good stead through thick and thin your teeth will show it.

Whatever the logic, pictures of leaders and crowd scenes from Iraq seem to me to be a good indicator of one's political affiliations. You may find it interesting to study the photos more carefully in the future. You will notice of course that ALL of the top government officials have impeccable dental health.

Since you wrote,
"Having served as a machinegunner during my military training in the northern parts of Norway, and having served in SFOR and KFOR, also as a machinegunner, I should have my share of experience with machinegun-belts in demanding conditions..."

and

"As the Norwegian Army still employs the MG-3 in the SAW-role . . ."

I assume that you were an MG-3 gunner? I have never had the privilege of firing an MG-3/MG-42, but have read only positive reviews of the weapon--critical, if at all, only of its rate of fire. Based upon the high regard in which it is held (it was a favorite of WWII MG guru Col. Chinn, and has attained cult status among US collectors and shooters), together with my own examination of its parts and principles, I have always regarded the basic design (with apologies to my fellow members, who seem to be more or less unanimous in their preference for gas-op designs) as a potential starting point for a future infantry system. Consequently, I was obviously surprised to read a thread suggesting a new MG design, originated by someone with extensive experience using my favorite MG, and would be extremely interested in your perspectives/criticism regarding its performance in the field.

Thanks,
Mike

P.S. I was just in your general vicinity (Estonia and Finland) for a conference, and have to compliment your cold-hardiness as well as your field experience. While I grew up with chilly winters (northeast Pennsylvania), the Navy generally tends to keep me where the water stays liquid. I haven't been that cold for years!

Yes, I was a MG-3 gunner.

I love the MG-3, but it is a GPMG, which means it can function in several roles, some of them better than others.

My opinion of the MG-3 is that it is excellent as a MMG, good as a HMG, and fair as a LMG.

As a LMG, the MG-3 is too heavy, cumbersome to carry, consumes too much ammo, and, because of the beltfeed, is vulnerable to the environment (snow, vegetation, mud, dislocated rounds)

Also, the belt in itself is a source of a few problems. If you use an ammo-box mounted on the gun, it needs to be small, because it will offset the CG for the weapon, and further complicates carrying because it is mounted on the left side. And because it is small, the gun needs to be reloaded quite often, which is quite time-consuming on a beltfed. If you dont use an ammo-box, the belt will get polluted and the rounds misaligned.

Of course in the MMG and HMG-role the MG-3 is spot on, because those roles are more static, and the supply of ammo is larger.

The biggest flaw of the MG-3 in the HMG-role is the caliber.

I think the MG-3 is a great design, but not the best choice for all roles...

My theoretical favorites in the different roles is:

LMG: Magfed in 6.5 Grendel
GPMG: Beltfed in 6.5 Grendel
MMG: Beltfed in .338 Lapua Magnum
HMG: Beltfed in .50 (or larger)

On the LMG concept without a belt:
Top feed often blocks sighting possibilities - what about a hopper that feeds through a side port - belt style without the belt?

Im not really familiar with hopper fed MGs...

The only one I know about is a Japanese WW2 MG, the Type-11, which was supposed to be surpassed only by the infamous Chauchat in flawedness...

As Im sure you know, the Bren had off-set sights. And about the mag blocking your vision: Try holding your hand in front of your face, mimicking a Bren-mag, and then focus on an object a few metres in front of you. Keep both eyes open, and you will notice that you will see straight trough your hand...

Maybe a side feed?

Just out of curiosity, why not a plastic chute, like the metal ones used for the Minigun? Yah, it ads weight, but not that much and it would keep the belt clean.

Feed it through the side opposite the gunner and have it eject down....or infront of the gunner so that he can moniter the feed (and again, the hot cases eject DOWN).

Well, setting up on the parade ground on a sunny Sunday afernoon that might be great, but these things do have to be maneuvered you know. Bobbing and ducking and weaving around the streets of Fallujah this sounds like a perfectly brain-damaged idea. Belts suck in these circumstances, that's why the Marines want ARs. Chutes? Uhhh, don't think so dude. The only thing wrong with the Bren top feed is not enough people have shot them. You can even eliminate paralax error using the side-mounted sights/scopes - well, at least the verticle kind. Why people are perfectly happy to have a scope 2" above the barrel but are freaked out by a sight 1" to the right is beyond me - especially since your shoulder is to the left of your right eye when firing from a bipod anyway.

Don't discount hopper feed so quickly...you could design a feed mechanism that picks up rounds in a circular belt or solid cylinder that holds several rounds in place against movement that rotates down to mechanically feed the chamber. The hopper portion should rely on a single stack that moves down through the hopper with gravity so no rounds get out of line before being picked up. You could zig-zag the rounds down preventing bouncing around. Look how the PS90 is turning rounds 90 degrees prior to feeding - not an idea many would have thought of trying in the past. I wouldn't recommend the hopper for other than vehicle or tripod mount.

I wouldn't want to try ducking, bobbing, and weaving with a belt fed weapon either (with a belt of any significant length ready).

Dobrodan,
Thank you very much for your quick, very informative response. You continue to surprise, particularly when you wrote,

"My opinion of the MG-3 is that it is . . . good as a HMG."

Our military reclassified heavy RCMGs as mediums with the introduction of Ma Deuce; I would have thought that the creators of Raufoss would be dedicated fifty-cal'ers as well.

"Of course in the MMG and HMG-role the MG-3 is spot on, because those roles are more static, and the supply of ammo is larger. The biggest flaw of the MG-3 in the HMG-role is the caliber."

In the contemporary HMG (anti-vehicle/point-AA/kill-through-cover) role, I agree with your assessment at the end of your post that the 12.7 or heavier is needed; of course, the M2HB in my opinion is a borderline cannon, man-portable (slowly and in pieces) from a ship's armory to a pintle on the 02 level (or from a Humvee to a tripod), and not much further; anything heavier, and I'd agree with those posters who favor the Vulcan/M113 vehicle. I've seen the CIWS Block1B in action, and (if properly maintained) it is a Phalanx in every devastating, unstoppable, kill-half-the-Persian Army sense of the word.

As far as the traditional MMG/HMG role, in which even the relatively-anemic .303 British round excelled in the Vickers . . . I don't know about your armed forces, but ours have evolved (devolved?) away from it, and from the art and science of machine-gunnery in general--where the design and placement of weapons, proper training and equipment for observation and fire control, tactics and organizational structure were far more important than caliber. The ability to mow down hundreds of men a mile away--and to harass and wound at two--with common rifle ammunition is dismissed as irrelevant due to its historically static nature, but the prospect of mass-wave attacks (a relative concept, as illustrated in past posts), together with long-term commitments in open desert environments, are very relevant, and tremendous advancements in both fire control and mechanization make the MMG, IMHO, more relevant to land warfare than ever.

It is particularly relevant to me in the Navy, where (outside the SEALs, of course) our idea of crew-served-weapon R&D is "What's the Army throwing out this year?" (or worse--"What's that cool toy he's running around with on TV?"). Don't get me wrong, we certainly have our goodies, and the CIWS certainly tops my list--but they are complex and maintenance-intensive, and require skilled techs to operate. We've been getting more lately--Mk19s and Mk44 Miniguns--but they are not universally issued, are often not mounted, and together with their accessories and ammo are too heavy to set up in a hurry; even the fifties, for whatever reason (corrosion, grit-producing topside maintenance, host-nation sensitivities inport) are not always up. From a dead stop (shipyard period, port visit to a hoplophobic country, or underway steaming where salt spray has led to dismounting of the fifties) the first responder is the M-60, and 3-5 round bursts don't cut it against massed small boats, low-slow fliers, or mobs swarming up the pier. What I'm looking into is a 21st Century Vickers--a rifle-caliber (if the service rifle is a Grendel ;)) or slightly larger (.338, .408, or a new .375 round I have in mind) MG that an individual sailor can carry in one piece, along with a box or two of ammo (in a backpack?) over a short distance (but possibly involving narrow passageways and steep ladders), drop into a pintle, tap into one of the countless freshwater-washdown connections piped all over the weather decks, and hose (by this time others will have arrived with more ammo, of course) until he gets tired of killin'. Interchangeable water-jacket and vented-tube barrel supports (a la the MG-15) might add versatility.

Keep shooting,
Mike

Mike,

Well, if you've read my PAV thread you know we are thinking along the same lines. You of course have much larger platforms to support such weapons, but even a PAV can use its hydraulic oil to cool a gun very effectively - and mortars too. We seem to be relying far too much on the infantryman's assault rifle for firepower and against human wave they just aren't going to cut it. I like the .338 in particular as it offers great range and terminal effects and is about as heavy as can be optimal against personnel. I suggested Bill look at an M14/SCAR-H configuration based on a 260 Remington or 7.62 NATO necked to 6.5 for longer range and more punch at range for the same reason. It would have most of the characteristics of the M14 - good and bad - but given the many advantages in terms of SD & BC I see little reason to be off to another caliber unless we are moving up to vehicle-mounted configurations where the .338 would shine.

For myself, I have concluded that if we want to field smaller armies than our enemies do, and we still want to prevail, we need to have EVERY man mounted in a vehicle that is their personal weapon so we can field the kind of 10:1 firepower advantage we will need. Whether skydiving, SCUBA diving, flying or driving, there is a great advantage to having gear you can customize and tweak to maximize your effectiveness. What I see in the US DOD, and to a huge degree in the Chinese system, is a lack of clarity about whether our troops will fight mounted or dismounted. This confusion is resulting in a very poor mix of weapons which lack both a heavy punch AND mobility.

A good start on fixing this would be the PAV, a .338 HMG, and an MMG using a Gast twin-barreled action with a 2-5,000 rpm ROF controlled by mass added to the action at the operator's discretion. Even if liquid cooled, the Gast will not likely be a 100% duty cycle gun, but it is very simple, reliable, and has a ROF high enough to do cordon operations well and can flat out knock an infantry charge flat on its ass at a point the mortar teams have pre-registered. For Naval ship defense in ports the GsH-23 would be awesome. http://club.guns.ru/wwwboard/message/eng/2742.html
http://en.wikipedia.org/wiki/GSh-23

Don't discount hopper feed so quickly...you could design a feed mechanism that picks up rounds in a circular belt or solid cylinder that holds several rounds in place against movement that rotates down to mechanically feed the chamber. The hopper portion should rely on a single stack that moves down through the hopper with gravity so no rounds get out of line before being picked up. You could zig-zag the rounds down preventing bouncing around. Look how the PS90 is turning rounds 90 degrees prior to feeding - not an idea many would have thought of trying in the past. I wouldn't recommend the hopper for other than vehicle or tripod mount.

I wouldn't want to try ducking, bobbing, and weaving with a belt fed weapon either (with a belt of any significant length ready).

If we keep the chute inside of an armored vehicle and use it to load loose ammo into 100 rnd mags THEN I think we have a great concept as the feed problems are not at the point of consumption, mags can be preloaded and stored, and the "Maginator" can be used for 20 & 30 ground mags as well in support of dismounted infantry.

Dobrodan,
Sorry I strayed there for a while, but your post really inspired me to think hard about some ideas I've been contemplating for a while. You wrote, "I love the MG-3, but it is a GPMG, which means it can function in several roles, some of them better than others." That pretty much says it all. If I had to sell my guns and commit to shoot just one for life, it would be an MG-42; at the same time, I sort of hate the fact that it (really, the MG-34) started the GPMG trend that led to the demise of medium machine guns capable of sustained fire in the naval role (the 240G comes close, but isn't quite in the same league as, say, a Vickers), and saddled "light" infantry fire teams with 25-pound guns. I have a few more more questions regarding your experiences that I hope you don't mind answering. You wrote,

"As a LMG, the MG-3 . . . because of the beltfeed, is vulnerable to the environment (snow, vegetation, mud, dislocated rounds)"

In what way? I understand the possibility of dislocated rounds, but with regard to the feed mechanism, I have heard that it has some unbelievable MTBF (140,000 is a number I've seen tossed around). Is this untrue? It certainly looks to have a lot of intricate, trinkety parts, but from everything I've read it's one of the few over-engineered designs that actually works. I'd be curious to compare the theory and my observations with your actual experiences in the field. The same goes for the rest of the mechanism, which seems to be one of those designs (like the Maxim, for instance) having so much clearance inside the rest of the receiver that you almost have to shovel dirt inside to make it jam. What area of the weapon is subject to grit-induced malfunctions?

You also wrote, "the MG-3 . . . consumes too much ammo . . ." Some regard its rate of fire as its greatest asset, the product of careful research into what characteristics would enable a relatively compact, man-portable weapon to hit just about everyone in its assigned fire zone. Since I have no experience with it, certainly none in combat, I'll defer to yours. I believe it would be relatively easy to reduce ROF--and to reduce its kick substantially in the process--by applying the constant-recoil principle (eliminating the heavy buffer spring, letting the bolt recoil against a longer recoil spring, through a longer receiver, and stop just short of hitting the buttplate before returning to chamber another round).

I wholeheartedly agree that "As a LMG, the MG-3 is too heavy, cumbersome to carry . . ." I believe that it is one of many fantastic weapons out there that could do with significant improvements--in this particular case, some serious weight loss. Grendelization would be a move in the right direction, and the use of modern, high-strength materials another. I don't see that being very difficult since, like most recoil-operated guns, its receiver stresses are very minor and very localized, and capable of further--almost complete--elimination (unlike gas guns, which except for certain cannon have fixed barrels that transmit the entire stress of recoil right into the shoulder or trunnion at the instant of firing).

TVMIA,
Mike

Actually, as a light and handy close-protection weapon for ships, a LMG in .50 Beowulf could be close to perfect...

As long as you keep it well lubricated, in a relatively clean environment, and feeds it good belts, it will "never" misfire... It will after a while, but only if you dont clean it once in a while... (after 5000rds or so, and only a quick cleaning...)

140,000 MTBF? I dont know, but possible...

Vegetation may block the feeding mechanism, and snow and mud may prevent the bolt from locking.

A heavier bolt will lower the ROF to 800rpm, but I have never used it.

If you want to use the constant-recoil principle, rebuilding a PKM would be easier than reconstructing the MG-3.

I have only held one PKM, but the quality of it surprised me... I was expecting the AK-47 feel, but nothing was rattling around... And it was incredibly light... To me it felt only marginally heavier than the G3-rifle...

http://www.usmc.mil/marinelink/image1.nsf/Lookup/2003866120
http://www.usmc.mil/marinelink/image1.nsf/Lookup/20038662520

Don't you just love the Bundeswehr camo uniform? It's so Waffen SS-ish. ;) :D

It's the most efficient, simple mechinism of all the machine guns. No gas crap to clog up, bind, and clean. Just mass and inertia balanced against recoil forces to perfection. The Grendel's short case would make it a perfect round for an action where both the bolt and barrel recoil for an even higher ROF. Heat, it's only serious drawback, could be handled by something like an ABS carbon fiber barrel. A Grendel's short case would make for a nice short trip back in recoil and equally quick return to battery. And please, no comparisons against the CTME gas action crap. It's a completely different GAS mechinism, with no recoiling barrel.

It's the most efficient, simple mechinism of all the machine guns. No gas crap to clog up, bind, and clean. Just mass and inertia balanced against recoil forces to perfection. The Grendel's short case would make it a perfect round for an action where both the bolt and barrel recoil for an even higher ROF. Heat, it's only serious drawback, could be handled by something like an ABS carbon fiber barrel. A Grendel's short case would make for a nice short trip back in recoil and equally quick return to battery. And please, no comparisons against the CTME gas action crap. It's a completely different GAS mechinism, with no recoiling barrel.

Thanks for heading off the "Whaddya mean there's been no modern development of the MG-42? There's the CETME, HK . . ." nonsense, that invariably seems to follow in a discussion along these lines, before it had a chance to begin. There is absolutely no comparison, as you so aptly described, between the 42--the most optimally-balanced action ever designed--and the StG-45-derivative roller-delayed-blowback weapons (which in high-power rifle calibers, basically constitute a bad idea made workable through some fairly ingenious workarounds). Of course, for lower-pressure rounds, I must admit the MP-5 (the action, that is; I'd prefer a bullpup configuration) is about the perfect solution for the SMG/PDW design problem--a slight delay that permits extraction at safe pressures, without a cumbersome and accuracy-destroying two- or three-pound bolt smashing back and forth as in previous, simple-blowback guns.

I've read with great interest some of your PAV posts (I have not (yet) read through the full main thread), being (bizarrely for a shipdriver, I know) somewhat of an old horse-cavalryman at heart. The vehicle seems perfectly in keeping with Guderian's understanding of the psychological, as well as physical, dimension of battle, leading to his realization that the panzer's engine is as much a weapon as its gun, a parallel with the cuirassier's horse and lance that resulted in the tank's modern employment as shock cavalry rather than mere SP artillery. Of course, (nearly) every time a tank, or anything remotely resembling a tank, is developed, it follows a knight's natural inclination, and evolves for the specialized mission of fighting other tanks. A PAV, on the other hand, would dovetail perfectly into the hussar/light lancer role of sprinting along and ahead of the heavies' flanks, scouting, finishing off or rounding up broken infantry, etc., in which it would compliment faster and heavier-armed, but more finicky and less reliable helicopters. It would even be quite useful to the Navy (along with the other services) for serving in the "wagon fort" (mobile firepower platform) role in base defense.

Take care,
Mike

As long as you keep it well lubricated, in a relatively clean environment, and feeds it good belts, it will "never" misfire... It will after a while, but only if you dont clean it once in a while... (after 5000rds or so, and only a quick cleaning...)

140,000 MTBF? I dont know, but possible...

Vegetation may block the feeding mechanism, and snow and mud may prevent the bolt from locking.

A heavier bolt will lower the ROF to 800rpm, but I have never used it.

If you want to use the constant-recoil principle, rebuilding a PKM would be easier than reconstructing the MG-3.

I have only held one PKM, but the quality of it surprised me... I was expecting the AK-47 feel, but nothing was rattling around... And it was incredibly light... To me it felt only marginally heavier than the G3-rifle...

Thanks again for a quick and informative response. I've never had the chance to play with a PKM, but I'm intrigued. Kits are available for a semi-build (although that would negate whatever constant-recoil benefits the weapon enjoys in open-bolt auto fire), but its price tag might strain the Mrs.' considerable (thus far) patience regarding my kit purchases (I picked up a few of my favorites in anticipation of the barrel import ban). I am, however, a recoil-op fan (for the same reasons Solidpoint described in his MG-42 post) and hope to continue my main thrust along 42 lines. Some regard constant recoil as some sort of arcane art, but it boils down to simply extending the recoil travel of the bolt. In an MG-3, using an extension rather than compression spring, I could have my constant-recoil cake and eat it too: short, light bullpup configuration (since it's already an ambidextrous bottom-ejector), provided I could develop a feed cover cheekpiece that would keep my face and the speeding belt from too close an acquaintance.

Take care,
Mike

Actually, as a light and handy close-protection weapon for ships, a LMG in .50 Beowulf could be close to perfect...

I believe the .50 Beowulf could even be capable of using multipurpose-rounds... Then it could be really devastating against small boats, such as the one used against the USS Cole in Aden... I know it would probably not increase armor-penetrating capabilities, but it would shatter softer materials...

The MG-3 is actually gas-operated, with the barrel basically being the piston.

You still need to scrape the "forward barrel rest", the "recoil amplifier" and the forward parts of the receiver. Unless you want do do it really well, you can do that in five minutes.

If the "recoil amplifier" gets clogged, the ROF will increase quite a bit, due to increased pressure.

... snip ... There is absolutely no comparison, as you so aptly described, between the 42--the most optimally-balanced action ever designed ... snip

... snip ... The vehicle seems perfectly in keeping with Guderian's understanding of the psychological, as well as physical, dimension of battle, leading to his realization that the panzer's engine is as much a weapon as its gun, a parallel with the cuirassier's horse and lance that resulted in the tank's modern employment as shock cavalry rather than mere SP artillery. ... snip ...

A PAV, on the other hand, would dovetail perfectly into the hussar/light lancer role of sprinting along and ahead of the heavies' flanks, scouting, finishing off or rounding up broken infantry, etc., in which it would compliment faster and heavier-armed, but more finicky and less reliable helicopters. It would even be quite useful to the Navy (along with the other services) for serving in the "wagon fort" (mobile firepower platform) role in base defense.

Take care,
Mike

Thanks Mike. I too get annoyed when any action with the word "roller" in it gets equated to an MG42 :rolleyes:

I was reading an old 1949 publication on the German Army's Blitzkrieg tactics at the start of Barbarossa and was shocked to learn that after the Stukas were done bombing a path open the very next asset follow on was NOT the tank, the horse, or heavy guns, it was MOTORCYCLES!!!

The heart of maneuver warfare, and what makes it so very effective, is you attack your enemy where he is totally undefended in rear areas. Now everyone should be able to image how little firepower it would take for a PAV force to sweep aside local LE while systematically ravaging power stations, water, sewer, rail, bridge, freeway, airport, microwave, cell towers, radio, TV, dams etc. To do this though one needs to move far and fast and be able to constantly be one or two steps ahead of bigger but slower moving forces. Once this cat and mouse game gets going it tends to shatter large enemy formations into many smaller ones trying to anticipate your next target. This makes it critical that PAVs, or any maneuver force, be able to destroy the enemy in detail. (and enmasse when the enemy is clustered) PGMs have solved the later problem provided large bombers can get to the target and stay on station for 10-30 minutes. (air supremacy is NOT required)

I had not thought about the PAV for naval defense. Could you flesh out your ideas on this? Putting a large prop and hydraulic motor at the end of the chariot boom, whether between a rig characterized by a set of flanking pontoons, or in the forward part of the bottomless V-hull of the starship, the engine's power can quickly and easily be retasked to drive the PAV forward. Power can be dynamically redirected too, so the wheels could be slowly turned to avoid drag while still acting as stabilizing floats. I have changed the V-6 engine spec a bit and am now using a slightly more powerful version that fits in the hull better and is built to last a half million kilometers. Based on my own 21ft boat with a 350 GMC truck engine the PAV's 315 hp should propel it along at 30knots or better in 3-4ft seas. The PAV's positive buoyancy, even when swamped, would be a great asset here and a great comfort to the crew I would imagine. This would allow it to keep up with the AAAV/EFV and even outrange it I believe. Small details like an onboard air-compressor and refrigeration unit which squeeze water out of desert air, and allow basic medical supplies to be carried onboard, work with its large fuel carry to dramatically reduce logistics. I seems to make almost every existing vehicle more effective. Ship, AAAV, chopper, IFV, or MBT.

We have been spoiled by having total command of the air for surveillance. McGregor has a little 5 page scenario set in the sandbox where this is denied us. I see this as being very likely as passive sensor systems which can detect even stealth aircraft make this a big problem. In such a scenario I see the PAV as being the eyes and ears of the DOD - searching for EAD installations and TBM sties and assisting in their targeting and destruction.

I first started working on the PAV (it seems a long time ago now) as I discovered a large hole in capabilities when I was writing and trying to move platoon sized forces quickly to make best use of heavy bombers being fleetingly on station with PGMs. A small force cannot afford to waste these precious opportunities, especially in the opening part of a campaign where air superiority is still up for grabs. Sleep is a luxury for the ground crews - as the real world A teams have often remarked on. Once I got the designed worked through with some good input here I realized that improperly employed they could get a lot of people killed, or properly employed, really kick some serious butt. I therefore began to really focus on tactics and the fine details. One of the things I really like about dobrodan's posts is his focus on the small details that make such a huge difference in battle. Those little details are a the difference between raw recruits and battle-hardened veterans.

Note:
One disturbing implication in recognizing that the very essence of maneuver warfare is attacking the undefended is that terrorist are in fact conducting the ultimate maneuver warfare. They attack unprotected targets deep behind your lines in small, swift strikes and then move on. (I of course loath their use of these tactics as civilian personnel tend to have been their targets, not infrastructure, and their cause is such a brain-damaged attempt to roll the world back to the 8th century - the last time they had any success. The year they ran the Arabs back out of Spain was - you guessed it - 1492. This speaks volumes for the Arab's petty infighting escalating to the point of social disarray.)

Solidpoint,

One does not need PAVS if you wan to knock out the civlians. Simply bomb all their powerplants, oil refiners, sewage and water treatment centers out of existence. Wait a few months and the population will starve to death.
Don't obsess about technology for your book. Worry about the STORY. Try to make it something that MIGHT happen in the real world but a type of story that hasn't been done before.

Well, that assumes the enemy has insufficient EAD to prevent you from flying bombers around in their airspace now doesn't it? It also assumes that you can find and identify critical targets with no land-based target designation teams, and that all such targets can be destroyed from the air. These are all nice assumptions which might partially work (we never were able to kill Saddam with all of our "Shock & Awe" airpower) if you are fighting 3rd world countries, but if you are fighting a near-peer, and we assume that our democracy will not be the party to initiate hostilities, it means they have IEADs, they have hidden and hardened the facilities of interest, and they will know when we are coming because they started the fight. As good as the IAF is they now believe with Syria's purchase of Russian SAM missiles they cannot operate in Syrian airspace - and those and better systems were also sold to Iran.

I don't think a story that relies on unrealistic assumptions works for me or the audience so I will not write "immaculate conception" scenarios where we "magically" appear in the battle with whatever we want with no discussion of how we got there, how we infiltrated, what we were doing there in the first place, how we will fight with what we do have, how we will be resupplied, and how we will maneuver and exfil. Iraq didn't have satellite surveillance, but China and Russia do and they provide it to other client states so we can see their assets, and formations and they ours - at least unless we or they have some technology to evade surveillance like stealth.

The fact is that in the real world we do need PAVs, the USMC is working hard to develop two such vehicles, and the missing capabilities I identified are the very needs the USMC has identified as those the ITV is intended to fill. I suppose there are stories to be written that ignore these facts but none which appeal to me. In short, I'll thank you to write whatever story you want and to please refrain from telling me how to write mine.

The fact is that in the real world we do need PAVs, the USMC is working hard to develop two such vehicles, and the missing capabilities I identified are the very needs the USMC has identified as those the ITV is intended to fill. I suppose there are stories to be written that ignore these facts but none which appeal to me. In short, I'll thank you to write whatever story you want and to please refrain from telling me how to write mine.

Oh, well EXCUUUUSE me. I mean, after having written 3 separate stories and getting rejection letters and speaking to agents, I guess I'm not qualified to tell you what they want. By all means, write a story that YOU like and see how far it goes on getting sold. Idiot!

Thanks again for a quick and informative response. I've never had the chance to play with a PKM, but I'm intrigued. Kits are available for a semi-build (although that would negate whatever constant-recoil benefits the weapon enjoys in open-bolt auto fire), but its price tag might strain the Mrs.' considerable (thus far) patience regarding my kit purchases (I picked up a few of my favorites in anticipation of the barrel import ban). I am, however, a recoil-op fan (for the same reasons Solidpoint described in his MG-42 post) and hope to continue my main thrust along 42 lines. Some regard constant recoil as some sort of arcane art, but it boils down to simply extending the recoil travel of the bolt. In an MG-3, using an extension rather than compression spring, I could have my constant-recoil cake and eat it too: short, light bullpup configuration (since it's already an ambidextrous bottom-ejector), provided I could develop a feed cover cheekpiece that would keep my face and the speeding belt from too close an acquaintance.

Take care,
Mike


Unfortunately, a MG42-action with constant-recoil-principle would not work.
You would probably have to redesign the bolt and the receiver, because to eject spent brass, the bolt has to hit the buffer.

The MG-3 is actually gas-operated, with the barrel basically being the piston.

You still need to scrape the "forward barrel rest", the "recoil amplifier" and the forward parts of the receiver. Unless you want do do it really well, you can do that in five minutes.

If the "recoil amplifier" gets clogged, the ROF will increase quite a bit, due to increased pressure.

Well, of course if we loosen the definition of gas that much all guns are gas operated - as the product of burning powder is gas. Even a blow-back design like the M9 is gas operated in that sense and requires cleaning after 10,000 rounds as well. I assume the recoil amplifier gets fouled at a fairly predictable and gradual rate so that if you get rushed by an infantry charge you can safely ignore it for another few thousand rounds or so?

I clicked thru on those links and there was one particularly good photo of an MG3. Just looking at the barrel shroud, bipod, and feed cover I could see a way to save 3-4lbs using aluminum or carbon fiber. The feed cover in particular would benefit a lot from being made of a fiberous construction as any breech explosion would be contained better by a fiber mesh than metal. I have a feeling that if one worked the problem a bit the M3 could be brought down to the weight of an M60. It might require a Ti bolt, SiN rollers, Ti clamps and a Ti or Ti faced aluminum receiver, but I think it could be done. Throw on an ABS barrel for an almost 4x increase in heat transfer and dissipation and that brings the effective ROF down to 300rpm from a heat management perspective and saves a couple-few more lbs. I think I might have discovered how to make the barrel liner out of ceramics too, (either SiN or TiB2) so make the barrel weight about half of the current or less. These materials are 3x as hard as tungsten and improve their characteristics as they heat. SiN is used to make "wear buttons" used to skid red-hot multi-ton slabs between rolling stations when forming roll-forming steel into sheet steel.

Trading in the 7.62 NATO for Grendel ammo to save weight (the difference in ROF between the M3 and SCAR-H is about the difference in ammo weight so it should be a wash) this would make for an awesome SOCOM weapon with utter reliability.

Btw, I saw a piece on the tension between Afghanistan and Pakistan about the latter doing their fair share to patrol the border and in the film footage there was a truck load of Paki soldiers with a top-of-cab mounted MG3. I knew from GlobalSecurity.com that POF made the gun and the ammo, but wasn't sure if the Pakis were still using the gun.

http://www.ceradyne.com/Products/Automotive.asp
http://www.ceradyne.com/Uploads/Armor_Materials_Brochure_1.pdf
http://www.ceradyne.com/Uploads/Improving_Ceramic_Armor_Performance_Article_1-06.pdf
http://www.ceradyne.com/Uploads/Silicon_Nitride_for_Cam_Rollers.pdf

Well, If you remove the recoil-amplifier, the MG-3 will actually be a beltfed, singleshot, bolt-action...
The plain recoil is not enough to make the weapon run. You actually have to capture the gas, and force it to push the forward barrel-rest, which is attached to the barrel.

The recoil-amplifier and forward barrel-rest dont have a problem with powder residues, but rather molten brass from the bullets.
This will lead to higher ROF if not cleaned, and will eventually make the gun unreliable until it is cleaned.

Unfortunately, a MG42-action with constant-recoil-principle would not work.
You would probably have to redesign the bolt and the receiver, because to eject spent brass, the bolt has to hit the buffer.

Excellent point; as designed, the MG42 action does require that it strike the buffer to eject spent cartridges. Since I would have to redesign the rear bolt anyway to utilize an extension spring and save length, I would definitely have to reconsider ejection. I'd probably either use a fixed inertial ejector mounted in the top cover (riding in a slit through or beside the feed stud) or have a shortened version of the present ejector hit a dogleg on one of the top rails (like the AK's).

Regarding your comment,

"The plain recoil is not enough to make the weapon run. You actually have to capture the gas, and force it to push the forward barrel-rest, which is attached to the barrel."

Has that been confirmed via experiment? I'm not sure that it can be, since (based on a cursory inspection of my parts kit) the booster seems to be an integral part of the forward barrel-support assembly. I've always been led to believe that the booster's function is to augment the rate of fire, and that the gun would cycle (but sluggishly) if it had a plain/open forward barrel bearing. If you have demonstrated or seen otherwise, again I'll defer to your real-world expertise. Clearly, though, since the MG-42 is bracketed by smaller- and larger-caliber guns operated by pure, unboosted recoil (the 1911 and M2HB, for example) it is undoubtedly physically feasible in a weapon of service-rifle caliber; it's just a matter of adjusting the recoiling masses and disengagement geometries. Whether that's advisable is a different question; even if it were theoretically possible to dispense with the booster, it certainly contributes to the gun's desirable characteristics. If recoil was not an issue (since the 42's muzzle attachment, like the Maxim's, 1919's, etc., uses gas vents to reduce chassis recoil while boosting barrel recoil), a simple bellmouth on the muzzle would suffice. Since recoil would be a consideration, particularly in a lightened gun (Solidpoint seems to have hit most of the particulars thereof), I'd prefer a modified pipe-tee brake, as utilized on artillery, tank, .50 BMG sniper, and PPSh guns. The design would not only permit the gunner to punch a wire brush through (with the action/barrel rearward, during lulls in firing) to avoid major fouling buildup, but would save about a hundred machining steps ;) .

Thanks again,
Mike

1. The ROF can be controlled easily by mounting one of several recoil amps.

2. The recoil amp, being a simple shape and getting hot can be easily replaced with ceramics saving weight, reducing gas etching and maybe even fouling.

I have a feeling I myself could make an 18lb Grendel version of this gun. The pics I have show a main bolt body made of simple cast iron. Nothing special needed here. Grendel case, 1/4th recoil, new alloys and ceramics would shrink the weight, size and recoil dramatically and be silly simple to maintain in the field. That recoil amp could be cleaned with a screwdriver, Leatherman or sharp rock.

I found this online:

"By 1974 the deficiencies of the M73/219 had overwhelmed even its most resilient supporters (See SOF, FULL AUTO, October '82) and tests commenced to find a replacement coaxial machine gun for U.S. fighting vehicles and tanks. The MAG 58 was pitted against the M60E2, M219, German MG3, British L7A2, French AAT NF1 (vehicular version of the AAT 52), Canadian C1 (Browning Model 1919A4 in 7.62mm NATO) and the Soviet PKM. By1975 all were eliminated except the M60E2 and the MAG 58. Heavy emphasis was placed upon reliability. Two criteria were closely examined: Mean Rounds Between Stoppages (MRBS) and Mean Rounds Between Failures (MRBF). Stoppages are malfunctions which require no more than a minute to clear. Failures require more than a minute to correct and usually involve component breakage. The test results were as follows.

Type Rounds Fired MRBS MRBF
FN MAG 58 50,000 2,962 6,442
M60E2 50,000 846 1,669
M219 19,000 215 1,090
Minimum specified 850 2,675
Minumun desired 1,750 5,500"

LINK (http://remtek.com/arms/fn/mag/)

Lord knows government test results aren't perfect, but it's worth considering...

Having been thoroughly satisfied with my (limited) experiences with the MAG-58/M-240G, I can't criticize the final outcome of this test. On the other hand, the mere fact that the M-60 (with its 846 MRBS--was it shooting blackpowder? And much worse--1669 MRBF, meaning every other jam "usually involve[s] component breakage"!? according to the specified criteria) won the "conference championships", so to speak, advancing to the Super Bowl along with the 240 over not only the MG3, but also the PKM and the (grossly overweight, nightmare to machine, but unfailingly reliable) Browning Thirty with "Heavy emphasis . . . placed upon reliability" calls into question the credibility of the whole test. Did they weld the other competitors shut?

Point taken. I've read enough about US government tests in The Black Rifle and other books to take them with a healthy dose of salt. Usually the entrant key players in the government want to win is the one that wins.

That updated RPD you mentioned above looks interesting.


I think scaling the basic FN MAG-58 design down around 6.5 Grendel and replacing the heavy rivited steel receiver with a short (from the breech area back to the locking shoulder) forged trunion inside a lighter stamped steel or reinforced polymer receiver would go a long way toward lightening it up. If you wanted to get exotic (ABS's carbon wrapping around a Stellite liner) I think you could make it as light or lighter than the M249.

P.S. It just occurred to me that they probably kept the '60 in that test (and cut it a lot of slack) because it was already in inventory...

Point taken. I've read enough about US government tests in The Black Rifle and other books to take them with a healthy dose of salt. Usually the entrant key players in the government want to win is the one that wins. . . .P.S. It just occurred to me that they probably kept the '60 in that test (and cut it a lot of slack) because it was already in inventory...

Oh, without question. It never ceases to amaze me how, having more or less eliminated aristocratic preferences from our personnel system, our modern democratic military nevertheless persists in lavishing "boss's nephew" treatment upon inanimate objects.

As an M-240 "satisfied customer", I think your MAG-58 idea sounds great. Your design sounds like it will use pre-headspaced extensions similar to those used in front-locking designs like the M-60 and MG-42 (if somewhat longer), but I am still confused as to how the basic design addresses the headspace issue. The diagrams you posted appear to illustrate a bolt that locks into a receiver shoulder (like the FAL), which would seem to require headspacing for every barrel change; based on my long-ago live-fire training with the 240, I'm almost certain that is not the case. Any ideas?

Take care,
Mike

I know the M240 is a fixed-headspace design, but I don't know exactly how its quick-change barrel design resolves the headspace issue. I'm not really proposing much besides (a) scaling the existing design down around the 6.5 grendel and (b) lightening the design up where possible (aft of the locking shoulder). The resulting MG would have good genes, if nothing else, being derived from John Browning's BAR via the FN MAG-58 - both time-tested combat-proven designs.

There's also some cool barrel technology emerging, but that is applicable to almost any design. I think wrapping a stellite liner using ABS's technology, perhaps with the active cooling system of the updated PKM (6P41 Pecheneg) would be cool (pun intended). The stellite would handle heat well and last a long time. ABS's carbon wrapping (with pitch impregnated resin) results in a lighter barrel that transmits heat more rapidly than steel and it sounds like the Pecheneg cooling system would carry that heat away more quickly than radiation and convection. All good things, but probably very $pendy...