Military Guns and Ammunition

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This is intended for people interested in the subject of military guns and their ammunition, with emphasis on automatic weapons.

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NGSW Phase 2 Consolidation and info   Small Arms <20mm

Started 30/8/19 by gatnerd; 105950 views.

From: smg762


yes there was a 300blackout SLAP from CBJ which presumably works well in most AR15s, i wonder about the accuracy in short barrels. do you think a smaller sabot eg. 6mm, would be more accurate than the usual 7.62 terms of keeping the bullet more concentric?

going back to MGs, have you heard of the RMK 30 (well, an autocannon). supposedly it had a combustible case.  i dont know if that mean't it was fully caseless. also wondered how a caseless approach could be safely combined with HE...

anyway i wondered about a .50 replacement that maybe had a more useful HE option....without going as far up as FN's massive 15mm gun.   Lets say you slighly upped the caliber to 13.7mm, and ultra long bullets (purely to hold more HE) . Then it could make a more usefull HE offering than the current raufoss round.


From: roguetechie


So one issue with the cbj sabots is that they're relatively bulky and heavy.

I think if you really wanted to do something like that your best bet would be something based off a high pressure but slightly trimmed back spc TV style neckless case ramped up to 80-85k psi and a lighter sabot design than cbjtech's. By going all but straight wall you could launch 5.56 sized projectiles with a 5-10 grain sabot weight to pretty lol high speeds while still being around the weight of a loaded 7n6 round.

Something like that using a relatively inexpensive and simple tool steel core inside a "gapless EPR" style projectile you could not only penetrate sapi's all the way to essentially full useful combat distance (200-300 meters) and your round would violently fragment out to beyond 700 meters while having sufficient fragmentation mass to seriously mess people up even at 700.

Coupled with a relatively simple recoil mitigation system in the stock you'd basically have a shooting experience a bit heavier than 5.56 but not anywhere near 7.62x39 recoil wise. This would be pretty easily controllable and would very likely represent about the best possible homogeneous squad if not platoon round.

Also, yes there's good reason to be looking at a .50 replacement and yes there's multiple ways you could go about doing this without making it particularly bigger or too much heavier in recoil while adding more payload capacity.

I believe that doing so would be very desirable too.


From: autogun


The CBG loading in .300 Blackout fires a 5.0mm calibre tungsten bullet weighing 6g (the sabot weighs an additional 1g) and has an MV of 725 m/s when fired from an AR-15 with a 406mm barrel. In Old English, that's a 0.20inch bullet weighing 93 grains (plus a 15 grain sabot) at an MV of 2,380 fps from a 16 inch barrel. 

Yes, the Mauser RMK recoilless automatic cannon family fired combustible-case ammo. It was marketed in two different calibres (30mm and 35mm), each of the calibres being in two different lengths. There is no reason why caseless ammo would have problems with HE shells - that's what most modern artillery uses.


From: DavidPawley


Seems to be a match to 123gr 6.5 Grendel in every measure except energy, where the grendel walks all over it.


From: renatohm


An interesting proposition, that's for sure.

It's always good to have options!

In reply toRe: msg 807

From: gatnerd


The CBJ looks cool. Biggest question is whether its capable of defeating Level IV. The use of CRISAT and steel plates is not particularly relevant.

Curious what CBJ would use for a training ball loading. Even a solid projectile made of Hardcast Lead (11.35g/cm3) would have a much higher velocity/different POI then the Tungsten Carbide (15.63g/cm3) loading. 

Tungsten = 94gr

Hardcast Lead = 68gr


From: Mustrakrakis


gatnerd said:

Biggest question is whether its capable of defeating Level IV.

Are we talking about alibaba Chinesium that may or may not meet NIJ 0101.04 Level IV, or actual military armor from a 1st world nation that's made to a more modern and sensible standard and inadvertently meets NIJ?  If you're talking about the latter, I'd say absolutely not.  A piece of tungsten moving at 2400 feet per second won't get it done unless it's the size of a basketball.  If we're talking about the former, I suppose that it might be possible, but I would have expected a picture of a busted vest in the promotional material if that were the case.

gatnerd said:

Curious what CBJ would use for a training ball loading.

OTS 110 grain loads at around 2400 FPS should be close enough for government work.  One in particular stands out:

Trajectory seems to be within an inch or two of the CBJ out to 300 yards, which is about as far as any sane person would want to shoot 300 BLK anyway, and they're lead-free to boot.  The downside is that this stuff isn't cheap, although it's certainly cheaper than tungsten sabot unicorn ammo.  However, any LEO agency using 300 BLK is probably already issuing this stuff for duty use, and if they're not, they may want to consider it.  I don't personally feel that qualifications and practice must absolutely be performed with duty ammunition, but there are plenty of agencies that do, and this is probably the round that you'd want for anything other than poking holes in 1/2" steel plates at 10m.  This option wouldn't work for most militaries (at least the ones that don't have lawyers as creative as JAG's are), but I'll bet that there are some non-expanding 110's out there that can be driven to 2400 without getting too spicy and will have a similar trajectory.


From: smg762


so like i said my thought for a replacement .50 would be a slight caliber increase (13.7mm) combined with extremely long bullets to get a high HE payload  - without needing a massive autocannon sized gun.

the other option is a massive bore, 16mm, with very low velocity HE shells to keep the gun small and managable. 

long range would be handled by a sabot... question is whether it poses a risk to friendlys when you shoot over them.

how would you approach a replacement to the .50, and would a belt fed-open bolt gun avoid the heat problem of, say, caseless .50?

also do you know how autocannons can handle the many APFSDS rounds i've seen, seeing as they don't have a smoothbore barrel? 


From: DavidPawley



M2HB gun only: 38 kg, 1.65 m oal 

ASP-30 gun only: 52 kg 2.02 m oal

ASP-30 uses same mounts as M2.

Neither is an IW.

30x113B ammunition natures are well developed and widely produced.

Your hypothetical.50 “extremely long” projectile won’t be stable, won’t carry any worthwhile HE and is ultimately pointless.

Your “huge” .60 bore has already been produced, then necked out to 20x102. That should tell you everything you need to know.

BRG-15 was proposed not because it was better than M2, but because CFE limited the number of 20mm+ AC permitted.

BRG-15 is an autocannon substitute, not a HMG upgrade.