Hk121

[stanc]

This would be better suited for conversion to 6.5 Creedmoor than to 6.5 Grendel, but I thought some of you would enjoy seeing it anyway.

http://www.youtube.com/watch?v=tQYngk6fpIg

[Variable]

Looks nice, but without anything to really go on, I wonder how it compares to the MG3? Send one to my address, and I'll put it through the wringer and report back!

Twer it me, I'd still chamber the CETME Ameli in Grendel and call it a day.LOL I'd be a might happy fella with one of those!

[mongoosesnipe]

I am a big fan of hk especial belt fed items i really want to get an hk21 when it becomes a financial viable option for me

[LRRPF52]

Looks like they're aiming to compete with FN in the belt-fed market. While lighter and more compact than the M240/MAG58, it's still too heavy at 9.9kg (21.8 lbs), but I like the overall layout from what I can see. It appears that they have adopted a constant-recoil principle, or are using an amazing buffer, because recoil management apppears to be very tame with this system.

The integral shell deflector on the ammo box is interesting.

Chambering in 6.5x47 Lapua is a non-starter due to barrel life on a belt-fed, and only suitable for a dedicated sniper system.

Since there is 11 years of 7.62 NATO currently stocked at present consumption levels, it is highly unlikely that we will see a viable logistical replacement for 7.62 NATO among the entrenched NATO countries, as much as I would like to see it replaced.

Do you know what type of operating system and locking mechanism they're using?

They could have cut a few kilograms of weight by eliminating the folding buttstock, and going with a German innovation known as the half-bullpup, like the FG42,MG42, or M60. I didn't see a reference to MTBF round counts, but I do like the rate of fire on this more than the M240.

If the MTBF is comparable to the M240, I wouldn't hesitate to select this over the M240, since it is lighter and more compact, with a purpose-built attached feed system for the gunner. From what I've been able to gather, this will be a replacement for the MG3 in the Bundeswehr, which is a good move in my opinion. Notice they made it back-compatible with the MG3 tripod, flex mount, and firing mechanism.

[stanc]

The integral shell deflector on the ammo box is interesting.

Perhaps done to save the fabric of the nut sack from being quickly abraded by the ejected cases?

Chambering in 6.5x47 Lapua is a non-starter due to barrel life on a belt-fed, and only suitable for a dedicated sniper system.

Well, I mentioned 6.5 Creedmoor as a way of introducing the thread, but some of the guys on Tony's forum would like to get an HK121 converted to this caliber as a surrogate cartridge for testing and demonstrating their GPC concept. The 6.5x47 Lapua case is likely too short for compatibility with M13 links.

Shouldn't barrel life with 6.5 Creedmoor be okay? After all, the Swedes used the MAG58 in 6.5x55 for a number of years.

Since there is 11 years of 7.62 NATO currently stocked at present consumption levels, it is highly unlikely that we will see a viable logistical replacement for 7.62 NATO among the entrenched NATO countries...

I agree, although Tony and his crew believe there's a chance of replacing 7.62 NATO with a 6.5 (or 6.86) GPC.

Do you know what type of operating system and locking mechanism they're using?

It appears to have a gas piston. Probably a rotating bolt, as with the 5.56mm MG4, but I don't know for certain.

Notice they made it back-compatible with the MG3 tripod, flex mount, and firing mechanism.

Yes. A good move, if it's to replace the MG3.

[Tony Williams]

I understand that the high weight of the gun is largely down to a very heavy barrel (as specified by the German Army, who will be adopting it as the MG5). In which case, producing a lightweight, more portable version shouldn't be a problem.

The purpose of an intermediate-calibre general-purpose cartridge would not be to replace the 7.62mm overnight, but to replace it in portable infantry weapons, thereby contributing to the weight savings the infantry are looking for. I would expect that vehicle-mounted 7.62mm MGs would carry on being used until they wore out.

[hellcat370]

It does seem to be a very well designed and thought out weapon system. I think a downsided version would be perfect for the Grendel, especially with the quick change barrel/length thing they have goin on.

[Variable]

I am a big fan of hk especial belt fed items i really want to get an hk21 when it becomes a financial viable option for me

I used to want one too, until I shot one. It was kinda akin to strapping your head to a paint shaker and then turning it on!LOL Just make sure you try one before you buy.


I thought the 121 did look pretty smooth, but the guy shooting it was probably pretty big too. I'd like to see a 170lb. 19 year old kid behind it next. That'd give a much better idea of what to expect.

[LRRPF52]

I used to want one too, until I shot one. It was kinda akin to strapping your head to a paint shaker and then turning it on!LOL Just make sure you try one before you buy.


I thought the 121 did look pretty smooth, but the guy shooting it was probably pretty big too. I'd like to see a 170lb. 19 year old kid behind it next. That'd give a much better idea of what to expect.

Roger that. The HK21 will rock your world, with its insane cyclic rate. It and the MG42/3 can't be fed by a dismounted gun team, unless you use the Wermacht 8-man MG42 gun team TO&E, and no modern military thinks of machineguns like the Wermacht did. 1100-1200 RPM is no joke in 7.92mm Mauser, or 7.62 NATO. This is why I prefer constant-recoil and a 500-600rpm pig for dismounts.

The Germans are much bigger boys, genetically. They often run at 6ft 2"- 6ft 4", 220lbs and up for a military weight guy in his 20's.

I'm all for keeping 7.62 NATO in the system, and letting the vehicle mounts eat it up, while fielding the MRLMG in 6.5mm. I wish I could command the R&D department for FN or HK for a year, and crank out the lightest belt-fed LMG, with the most effective range, and least recoil.

About the soft ammo bags for the SAW: The top portion of them is made from a very thick, strong plastic, that holds up well to Infantry abuse, and the SAW ejects out the right side, while this HK121 is a bottom eject like the MAG58/240.

[stanc]

...the MG42/3 can't be fed by a dismounted gun team...

That's a curious statement, seeing as how there are videos showing the MG3 being used by dismounted infantry in Afghan operations. For example:

http://www.youtube.com/watch?v=yLAwAY-YCG0

[LRRPF52]

Because of the cyclic rate, it can't be fed for long. Notice how many times he had to change belts, especially as a one-man gunner with no AG, AB, AB2, AB3, AB4, AB5, Gun Team Leader, like the Wermacht employed. They had basically a gun squad with loads of MG34/42 drums hanging from them, but it still takes too long to change drums with that weapon in a maneuver role. In the defense, fed from ammo cans or prepped belts, it's great, but not in a dismount role. I have experience actually using it in that capacity, and it blows.

This HK121 is a step in the right direction for dismounts, but 7.62 NATO will still limit the amount of ammo and fight focus the gunner will be able to maintain.

[stanc]

My understanding is that riflemen in an infantry squad/platoon are typically tasked with carrying extra 7.62x51 linked ammo for the M240/Mk48 machine gunner. Anybody know how much 7.62 ammo is usually carried by a rifleman? 100 rds? 200 rds? More?

[LRRPF52]

It depended on the mission and units I was in. Riflemen seemed to get stuck with all the extras when it came time to distribute AT4's, CLS bags, litters, extra ammo for the SAWs, and linked 7.62 for the M60 or M240.

When we had LCE's with buttpacks per unit SOP's, the buttpack would often get 100rds of 7.62 or a SAW drum, or linked 5.56. We often kept the 7.62 linked in the cardstock boxes it came in when distributing them out.

I'd be interested to hear what other units have done as well. We generally kept the 7.62 linked with the gun teams and weapons squad in most line units I was in, since we had Ammo Bearers and Assistant Gunners, in addition to Machine Gunners. It really sucked when we had 2-man gun teams, and I was the AG/AB as a young PFC, because that meant I carried:

* My rucksack with packing list
* M122 tripod (steel)
* T&E mechanism (steel)
* Pintle (steel)
* 1200rds 7.62 linked
* M22 Steiner binos (heavy, large)

In the winter, my rucksack alone weighed 120lbs, and took the Weapons Squad Leader and my Gunner to lift me up after I had gotten into the ruckstraps on the ground, with one of them holding my weapon. I kept 150rds+ inside a large pouch on my LBV on the right side to attach to the gunner's starter belt.

The US has failed its infantry soldiers for decades by not having an on-gun linked ammunition solution for the 7.62 belt-feds, and it hasn't been until recently that certain units developed and paid for COTS solutions to this problem with the M240.

The PKM was issued from the start with a direct-attach ammo can/drum for linked 7.62x54R.

[Trooper]

The SAW fires cartridges in intermediate calibers (5.56x45, 6.5 Grendel). The M240 (general purpose MG), which this weapons appears to be in the same class, fires cartridges like the 7.65x51 thus the .260 Remington (6.5x51) could work.

the NRA American Rifleman had an article about two months ago on the Army sniper cartridges. It mentioned that the 7.62x51 was not being used as much for snipers but rather in the Designated Marksman program. That snipers were moving more towards the .300 Win Mag and the .338 Lapua. Also that the Army had developed a heavier .300 Win Mag bullet (200 gn) that gave similar results to the .338 Lapua. Which had me wondering whether it might be possible to convert the M240 to .300 Win Mag?

[stanc]

Which had me wondering whether it might be possible to convert the M240 to .300 Win Mag?

Not likely, due to:

- Cartridge OAL
- Belted case