New Cartridge Developments and Implications for Dismounted Infantry Soldiers

[stanc]

On-target performance would address human targets first. Since every person reacts to projectile injuries in different ways, I would like to see an upgraded standard to ballistic gelatin representing:

* Tissue compartmentalization
* Bone structures
* Body heat
* Clothing/Equipment
* Skin and sinew
* Anatomical orientation

Clothing and equipment -- such as loaded AK mags in chest pouch -- is already done. The other items you propose not only strike me as an unnecessary complication, but would mean that no two bullets would strike the same bone structure or organ compartments in the same way. There's an infinite number of anatomical orientations that could be used, all of which would give different results. And I don't know how you could test for variations in body heat, since ordnance gelatin is supposed to be kept refrigerated until use. :confused:

Most of us would postulate that long, high-sectional density bullets would be superior to the currently available projectiles in such tests, but that has to be demonstrated.

To be sure.

Barrier target performance would include defeating foreign trends in armor, common construction materials for walls and structures, light-skinned military vehicles (will this be able to reach the occupants, and from what angles/aspects), as well as various types of trees. I would propose demonstrating this on several examples, illustrating the capabilities and limitations, with existing calibers from existing platforms as comparisons.

I doubt that hard body armor can be penetrated by ball ammo, be it M855A1-type or conventional FMJ. Other than that, I concur with the other proposed barrier tests.

[bwaites]

I doubt that hard body armor can be penetrated by ball ammo, be it M855A1-type or conventional FMJ. Other than that, I concur with the other proposed barrier tests.

Why? It can be penetrated fairly easily with the right velocity and projectile. My 7mm WSM blows through steel plate that AP 308 barely penetrates.



The little penetration holes are the penetrators from .308 AP, only the penetrators made it through the plate. The big holes are 180 grain Berger VLD's, they blew through, making holes literally twice the diameter of the bullets. Thats an open tip, match bullet, not a penetrating bullet. I seriously doubt that plates that would be cracked by 7.62x39 would tolerate that Berger.

If you meant that making a 6/6.5mm bullet from a carbine do it, I understand. None of the Grendel loads I tried made it through, Including AP 130 grain loads, though I haven't tried the 110 grain AP loads yet. I think velocity has a big part to play in AP penetration.

[LRRPF52]

There's an infinite number of anatomical orientations that could be used, all of which would give different results. And I don't know how you could test for variations in body heat, since ordnance gelatin is supposed to be kept refrigerated until use.

stanc,

That is one of the biggest problems I see with ordnance gelatin. While it may represent a standardized medium that projectiles can be compared in, what relevance does it have to wound characteristics in living human beings? A cold gelatin medium might be closer to what brain tissue is like on a corpse in the morgue, but not the breathing chest of a human at 98.6 F. Basic physics tells us that a fluid dynamic environment at higher temperature will provide less resistance to a projectile, just like the wind. We therefore can derive very little from cold ballistic gelatin in a large container if we are trying to extrapolate the results to a dissimilar target.

If we are to move closer to establishing predictive wounding characteristics based on shooting something other than the actual intended targets, I would propose simulating as many variables as possible, though what I would recommend is admittedly cost-prohibitive...for individuals and small companies. The necessarily-complex target I described would also facilitate multiple shots in many locations, since there would be compartmentalization, with each organ compartment requiring less tissue-simulating medium per volume. It would also make a great training aid for end-of-course shooting tests in many competitive, evaluative, and instructional settings.

Rather than simulating an unreasonable number of anatomical positions, I would suggest a simple fractional model from at least 3 frontal angles in the transverse plane, with varying elevations on the coronal plane, as well as side penetrations on the sagittal plane at varying elevations, to include arm penetrations with and without through-and-through wounds to a simulated humerus. I would also like to see a representation of the pelvis in the ballistic mannequin. A self-healing polymer skin surface could enclose the torso, with replaceable inner components for repeated testing and cost-effectiveness. That is what I would like to see.

If standard gelatin were to be used as an interim solution, I would lean towards heating it at least, and arranging a ladder of wet wood rungs in front of it to simulate ribs, with a .50" rubber mat in front of that to simulate the epidermis, dermis, and hypodermis.

LRRPF52

[BluntForceTrauma]

Stan, Liberty Ammunition is here: http://www.libertyammunition.com/Lead_Fr...RTY_T.html

Unless I'm mistaken, Liberty makes the M855A1 projectile. Any way, here's an M855A1 link from a year ago which makes some points relevant to our discussion: http://bulletin.accurateshooter.com/2010...ghanistan/

On Mk318: http://bulletin.accurateshooter.com/2010...5-56-ammo/

John

[stanc]

Why? It can be penetrated fairly easily with the right velocity and projectile. My 7mm WSM blows through steel plate that AP 308 barely penetrates.

If you meant that making a 6/6.5mm bullet from a carbine do it, I understand. None of the Grendel loads I tried made it through, Including AP 130 grain loads, though I haven't tried the 110 grain AP loads yet. I think velocity has a big part to play in AP penetration.

Certainly, if you get the velocity high enough, as with your 7mm WSM, you could no doubt defeat hard armor with ordinary bullets. But this thread -- and Tony's -- is about service ammo, fired in 14.5-20" barrels, most likely at less than magnum velocities. Neither 5.56mm M855/M855A1 Ball nor 7.62mm M80 Ball will defeat hard armor, and I still think it most improbable that the hypothetical 6/6.5/6.8/7mm service ball cartridge will do any better.

[BluntForceTrauma]

Regarding bullet lethality, I'm of the thinking that caliber in non-fragmenting bullets is much less important than shot placement. Pulling a number out of the air, I'd say 90% of lethality is shot placement, and merely requires of a bullet the velocity, construction, and sectional density to penetrate barriers, gear, and body mass to reach vital structures. The remaining 10% wherein we DO give a nod to caliber size, is more relevant to fragmenting bullets whereby a cloud of particles effectively increases the frontal area of the bullet and increases the odds of hitting a vital structure (we've been through all this before, at any rate).

Contrary to the fad of and fans for lethality via fragmentation for the past, oh, ten years, the latest U.S. military cartridges, M855A1 and Mk318, are largely non-fragmenting designs.

So I look at it this way: An icepick hole made by any bullet in the spectrum of 5.56 through 7.62 is going, in my theory, to be barely discernable to the enemy target. Slight differences come into play when yaw is introduced, and a longer bullet tears a larger swath.

So what role DOES bullet caliber play? External ballistics and barrier penetration, for the most part. There one seeks an optimum balance between caliber and bullet length and shape.

John

[Tony Williams]

Of course shot placement is the main determinant of effectiveness - the most impressive ubermagnum isn't much use if it misses the target - but against that you have to set the testimony of many soldiers who have used both 5.56mm and 7.62mm NATO weapons in combat that the 7.62mm is far more effective in that it puts the target down promptly a much bigger percentage of the time. Despite the fact that the 7.62mm M80 has a slow yaw performance and doesn't fragment.

[stanc]

Stan, Liberty Ammunition is here: http://www.libertyammunition.com/Lead_Fr...RTY_T.html

Thanks. Although their site really, REALLY bogged down my ol' computer.

Unless I'm mistaken, Liberty makes the M855A1 projectile.

Their "T3" sure does look like an M855A1.

As for making a 6.5mm version, I was calling for that a year ago (and bugging the 68forum guys about a 6.8mm version, too).

Attached: 5.56 / 6.5 / 6.8 / 7.62

[stanc]

Contrary to the fad of and fans for lethality via fragmentation for the past, oh, ten years, the latest U.S. military cartridges, M855A1 and Mk318, are largely non-fragmenting designs.

I'm afraid you're in error, John. M855A1 is a fragmenting design. It yaws, then breaks apart into three or more fragments -- steel penetrator, copper slug, and jacket (which may tear into two or more pieces).

As for Mk318, it expands similar to a Barnes TSX, and the four "petals" may break off, thereby creating up to six fragments, as the non-bonded lead core typically separates from the solid base.

[warped]

It's all about retained energy and terminal performance resulting in tissue damage (I must have slept in a holiday inn once)
And as Tony said and I have said for many years, shot placement trumps all.

[warped]

None of the Grendel loads I tried made it through, Including AP 130 grain loads, though I haven't tried the 110 grain AP loads yet. I think velocity has a big part to play in AP penetration.

Yep it is all in the math Bill, E=MV2/450400 (muzzle) but if we determine that we retain enough of that a BB would make it through a plate of 4" thick steel if it were moving at 28K fps

[LRRPF52]

Gents,

While I acknowledge the importance of projectile design, I think the weight, profile, and handling characteristics of the machinegun are more important. Using a constant-recoil operating system will increase hit probability drastically, and untrained soldiers need very little time with such a weapon to be effective with it, since it's pretty much an aim and shoot = hit procedure. I posted some about this before the forum was destroyed, with links to video of the Ultimax, KAC LMG, and Kp31 Suomi submachinegun. You simply have to experience the shooter bliss that firing these types of weapons is, as you can basically write your name with them. Well-trained soldiers are simply lethal with them, as the Finns proved in 1939-1940 against the Soviets.

They were basically using a 9mm subgun in the capacity that we use SAW's in today, that is how effective constant recoil is, and they stacked bodies until guys had to be pulled off the front line because the psychological weight of how many humans they had killed was unbearable for them to sustain. Keep in mind that they were shooting 9mm at guys fully-kitted out in winter gear, and still had that effect. They were also in way more enclosed terrain than one would find in Afghanistan, but the effectiveness of that system is a matter of historical record.

When you look at the recoil of the SAW or AK, it is not conducive at all to keeping even short controlled bursts on-target, unless you muscle the crap out of the gun and drive it hard. The M240 on a flex mount was very good, but then they got rid of the flex mounts and installed a new buffer in it, which basically made it feel like constant recoil when the buffer was new. I protested about losing the flex mount..until I shot the gun with the new buffer. You question if you have even fired when there is no felt recoil. The 240 was already a laser gun, but then it got even better. Notice that these features are what Joe loves, but hates the weight.

Regardless of what high-power ammunition is used in an LMG, as long as it has a constant-recoil mechanism, a novice gunner will be able to keep almost all the rounds on-target, and multiple hits of even a mediocre projectile design will ventilate a human target quite destructively. When I think about the capabilities of a Multirole LMG with the ballistics of a 6.5 Swede, I get excited. If one were to compound that with a well-designed projectile that penetrates barriers and fragments in tissue, it would be all the merrier.

I want to reiterate the role that LMG's and GPMG's play in Light Infantry tactics...it is a dominant one. Whenever small unit tactics are being discussed, we always talked about how the 7.62 machineguns represented 50-66% of the firepower of the whole platoon, or figures like that. A belt-fed weapon brings a decisive amount of firepower to any land force encounter, and is usually one of the most addressed components of planning when discussing the details of actual actions on the objective for deliberate attacks, raids, ambushes, defenses, and Immediate Action Drills.

While the guns may not be as sexy as sniper rifles or good marksmen, when they talk, everyone listens. The art of machine-gunning is too often overlooked on the outside, but it is a noble and coveted position in the Infantry. I'm in favor of giving gunners a super-light gun that tracks easy, with a superior cartridge, that they can also fight in the streets with when necessary.

LRRPF52

[BluntForceTrauma]

I'm afraid you're in error, John.

Thanks, Stan. I'm happy to be corrected in order to base opinions on the facts as they stand.

John

P.S. By the way, LRRPF52, I greatly appreciate your inside info and theory based on sound, on-the-ground observation.

[stanc]

While I acknowledge the importance of projectile design, I think the weight, profile, and handling characteristics of the machinegun are more important.

I agree, but we've been discussing projectile design because that's a vitally important part of what the thread is about -- new cartridge developments.

[stanc]

Thanks, Stan. I'm happy to be corrected in order to base opinions on the facts as they stand.

No problemo, John. Hey, any ideas for implementing your proposal to convert a KAC LMG to 6.5 G as proof of concept? It'd be super to get a belt-fed Grendel operating after all these years of talking about it.

[LRRPF52]

I agree, but we've been discussing projectile design because that's a vitally important part of what the thread is about -- new cartridge developments.

stanc,

It's also essential to have a new cartridge if any hopes of replacing the 2 current US shoulder-fired belt-fed machineguns with a single platform will be realized. The fact that cartridge developments are what they are now is what I think makes this new Multi-Role LMG a greater possibility in the near future.

If the KAC LMG receiver was oriented in a half-bullpup configuration like the FG42 or M60, it would allow more barrel length to get velocities closer to 2800 fps with 6mm-6.5 projectiles. I'm thinking of an entirely new true bullpup design, that uses a simple "nutsack" solution like we used on the SAW, since feed-source location is much more problematic on a bullpup when using a box-shaped, versus straight magazine behind the pistol grip. With a little pig less than the length of an M16A2, you could still have a 24" barrel length and the first truly ergonomic design for gunners.

Every machinegun I have shot, carried, or played with almost always has horrible ergonomics with regard to: 1) firing hand interface, 2) cheek weld, 3) eye-height relationship to sights, 4) carrying interface, 5) Center of balance, and most Western GPMG's have no provisions for mounting a drum or box to feed the gun with in a maneuver or practical environment.

The MG42, HK21, and PKM are exceptions to the lack of attached feed source, and several designs have been field-rigged for the M60 and M240, but they were not part of the Basic Inventory Items of the US GPMG's when I was in. They just expected the gunner to rely on his Assistant Gunner for supply of ammunition, after burning through a 50rd starter belt. I must tell you that is one vulnerable feeling when you're humping a 30lb hunk of steel. Compare that to some bugger-eater running around with a PKM and its attached 100rd/200rd/250rd ammo can.

Is it starting to make more sense now when I say, this end of the equation is broken? It just shows how tough and tenacious our guys are, especially when you look at the ridiculous loads they carry versus anyone we've fought in that past 50 years, and the overwhelming combat successes the US has displayed in dismounted warfare. I say we give Joe a break and increase his firepower and maneuver capability in one sweep.

LRRPF52

[bwaites]

Yep it is all in the math Bill, E=MV2/450400 (muzzle) but if we determine that we retain enough of that a BB would make it through a plate of 4" thick steel if it were moving at 28K fps

10-4, I was being a little facetious when I mentioned the velocity issue. I was stirring the serious pot these gentlemen are cooking, because I don't believe the velocities discussed are sufficient for true hard armor AP capability.

However, I'm wondering now if I can drive a 110 grain AP round at 2800 FPS if it will penetrate 1/2 steel, which has been my test medium so far. If so, I think that would get through hard armor as well.

Going to have to give it a try!

[stanc]

LRRP,

Sure, the characteristics you desire in a GPMG make a lot of sense. It's just that, other than saying I agree, there's not much more to say.

Heck, after 6-7 years of discussion, we still can't even get an existing belt-fed LMG converted to 6.5 Grendel. How are we going to design -- let alone build -- a completely new weapon? :confused:

Stan

[LRRPF52]

Bill,

What do you think about the ballistic mannequin idea I talked about earlier in the thread? Do you know of any CPR mannequins that are unserviceable, looking for a new, loving "home"?

Tony Williams,

Have you ever done a weight analysis of 6.5x55 Swede with 140gr versus 7.62 NATO, assuming equal weight links?

Stanc,

Heck, after 6-7 years of discussion, we still can't even get an existing belt-fed LMG converted to 6.5 Grendel. How are we going to design -- let alone build -- a completely new weapon?

I'm glad you asked...

Re armor:

http://www.defence.pk/forums/china-defen...armor.html

LRRPF52

[LRRPF52]

Guys,

We're 12 years into a new century, with a plethora of old weapons from the last century, with more capacity to envision, design, prototype, RDT&E, and market new products than anytime in history. Someone will meet current & future demands that are unsatisfactorily being met by the default inventory right now.

All I see is opportunity, which combined with the ability to share information like never before, should result in revolutionary developments that are long overdue.

The field is ripe boys...

LRRPF52