Us army ITT for new dmr a gpmg / lsw in 6.8

#41
GPMG isn't an MMG, it was an LMG in my day. Pfft kids
Ah, what I meant was why would one create a MMG ? It can't be as portable as a gimpy with a decent ammo load. Chances are it will be a static or vehicle mount, and the .50 cal covers that.
If however, we went an intermediate 6.5 -7mm round for small arms and got rid of the 7.62, then .338 might represent the next step up. Somehow just can't see it as being that great. Its powerful, but not as handy.
If one can call 200 link and a gimpy on a sling handy, that is.
 
#42
I think the upgrade to the M240 proposed was an attempt to reach out to .338 ranges with a portable gpmg. I know the GPMG SF kit will go far enough but its the yanks after all.
 
#45
No arguments from me there but i did not suggezt making the guns lighter, the target weight of an m4 with all that shit on it (red dot, magnifiers, ir laser and light) is fine. We can make the ammo lighter by using plastic cases instead of brass or steel...in theory anyway. If it can feed in a m2 then it can feed in an fn mag. I thought that the current sticking point with plastic cases was trouble feeding from mags due to friction or something like that?

Sounds like a problem that could be solved if there was am apetite for it
IIRC The Hun tried caseless and abandoned it, as the heat of the exploding propellant was in large part carried away by the brass casing, which wasn't the case with plastic.

Aircraft mounted weapons will benefit from air cooling assuming their not in the hover.
 
#46
The velocity and energy results seem appealing though


7.78 g (120 gr) sst2,460 ft/s (750 m/s)1,612 ft⋅lbf (2,186 J)
Mass delivered downrange is for winners. We outperformed .308 with 120 grain 7mm in the .280, no reason why the round shouldn't be developed further.
 
#47
which wasn't the case with plastic.
The polymer trials though have used a different approach, if you read the link the replacement for traditional as opposed to telescoping uses a case base like a shotgun cartridge does. This does provide some heat sink. The heat problem using partial polymer cases has to a large extent gone away!
Telescoping well it remains to be seen!
 
#48
#49
#50
I'm damn sure I was running around stanta when I came across a pile of fired plastic cartridges with a metal base in an obvious fire position. They were shaped like a live round except that the tip was split in 4 places so it would petal on firing. The declaration at endex meant I couldn't hang on to one to find out more. Given that most rifles fire from a closed bolt, and the absence of link, the material must have been suitably heat resistant. This was a good few years ago.
 
#51
I'm damn sure I was running around stanta when I came across a pile of fired plastic cartridges with a metal base in an obvious fire position. They were shaped like a live round except that the tip was split in 4 places so it would petal on firing. The declaration at endex meant I couldn't hang on to one to find out more. Given that most rifles fire from a closed bolt, and the absence of link, the material must have been suitably heat resistant. This was a good few years ago.
Training blanks, we also used to use a low power live round for NITAT
 
#52
Ah, what I meant was why would one create a MMG ? It can't be as portable as a gimpy with a decent ammo load. Chances are it will be a static or vehicle mount, and the .50 cal covers that.
If however, we went an intermediate 6.5 -7mm round for small arms and got rid of the 7.62, then .338 might represent the next step up. Somehow just can't see it as being that great. Its powerful, but not as handy.
If one can call 200 link and a gimpy on a sling handy, that is.
It may have started out as someones pet project they managed to get traction with some friends on board. Look at their on again, off again, now back on 9mm SMG project.
 
#53
Mass delivered downrange is for winners. We outperformed .308 with 120 grain 7mm in the .280, no reason why the round shouldn't be developed further.
develop .280 further? I dont see why not other than we might as well put the effort into making the cases lighter if we are developing new / resurrecting ammo.

.280 with the aluminium cases would probably be just fine as it is
 
Last edited:

ugly

LE
Moderator
#54
No I was talking about 6.8 spc, its still got loads of potential. I wouldn't use ally cases. The 6.8 would probably top out at 140 maybe 150 grains until powder developments move on again.
 

Latest Threads

Top