Next Gen Squad Weapon in 6.8 moving forward in 2021 PB

Status
Not open for further replies.
The other issue to remember is that Army wants a harder hitting SAW, not a newer AR.
The premise of a SAW--Squad Automatic Weapon--is to provide cover fires in both offense and defense. So, it really needs to be able to outrange the rifles in the squad.

The 249 was meant to use its slightly longer & heavier barrel to this end. It also used belted ammo to keep the round count up as well. So, the doctrine was that you were meant to apply the SAW to targets in the 300-600m range, typically in suppression mode. The reality was that most squads were not engaging much beyond the 300m range of their own rifles. And, that when used at longer ranges, the 5.56 ammo was having direct effect on opponents. The Infantry Squad already being overloaded as is, could not just be given an M-240 in 7.62nato. (Doctrinally, that belonged to the Platoon and Company level of fires, and more importantly, of Supply.)

What to do, then. Well, find an intermediate between 5.56 and 7.62. So, there has been a very long search to figure out what "light" projo is "heavy" enough to the task. This winds up being somewhere in the 6.5 and 6.8mm range.

The military often identifies a round first, then orders up weapons to use it. There's a theory that using a clean slate offers innovation on that front. The boffins seem to feel that the consensus will fall in somewhere in 6.8 bore, and from 45-50mm long cases. Seems logical. even if we are quibbling over 0.02mm to not just call the new round 7x45 or 7x50.

Now, it will be interesting to see how Infantry copes with having an additional caliber to hump into the field. Or if the tactical advantages of the ammo over-rides the supply complexity. No major military has tried fielding three calibers at the Company level successfully. Which does not mean it's a bad idea, just that there's no prior experience in doing that.

Will that generate a new chambering for non-military arms? Maybe. May depend on if over-run ammo gets put on the public market or not.
 
CapnMac, These cartridges are not intermediate between 5.56 and 7.62x51. They have nearly 30% more muzzle energy than M80. The purpose is to replace all of the squad infantry weapons with this common cartridge. The performance is very close to a modern loading of a .270 Winchester. The rounds I have specific knowledge of are spitting out 120 gr projos at 3200fps, with an objective of 3400fps, compared to M80 with 150gr at 2800 fps.
 
The purpose is to replace all of the squad infantry weapons with this common cartridge.

So my question would be if this is the case. The 6.8 round is going to be 40% to 50% heavier than the 5.56. Given the same load out does a soldier really want the reduction in the amount of rounds they can carry? To me if I am going into a close quarters situation I want as many rounds as possible.
 
Part of the spec included lightweight ammo requirements which is part of why there are hybrid and polymer cases in every proposed system.

The extra ammo won't mean much if you cant punch their body armor.
 
And the original idea behind a squad automatic weapon was to share the same ammo as the rifles. That is why the M249 is also chambered in 5.56 and can use M16 magazines in a pinch if belts run out. When I was in the Army, you had 1 SAW per squad and usually 2 M60 medium machine guns per platoon. I was usually one the the M60 gunners.

If they do go with the Sig 277 hybrid round, then there won't be a need for both a SAW and M240 medium machine gun (M240 replaced the M60). Having the ability to share ammo with all weapons assigned to a squad/platoon is very helpful.
 
Owen:
This is being driven by the ubiquity of lightweight level IV+ body armor appearing worldwide.

I'm sure, partially, lately. But the entire history of the 5.56 NATO round has been "how can we soup it up to make it more effective?"

To the point where the case has been thickened (so much for "saving brass") and the pressure raised to what, lately 65k or more, and the bullet weight to 62gr (and more?) and the freebore increased to (I think) three inches now. Yeah, I kept thinking, "Every round is a proof round nowadays." :what:

So the advent of more effective body armor has finally pushed the power question into reality: "Hey, maybe we should just dumpster that jungle-style tree-denuding varmint cartridge and go to a Jack O'Conner-style cartridge, yes?" :)

Amusingly, civilian shooters keep coming up with new wildcats to fit in the magazine (some of which have become fairly commercial) to improve the 5.56's rather limited capabilities.

Silk purses, sow's ears...

So frankly I pretty much gave up following the military's fruitless pursuit of power in the .22 caliber range because every time I heard of another "improvement" over the original M193 cartridge I spewed coffee all over and just laughed and laughed and laughed...:rofl:

Terry
 
Last edited:
Has anybody ever asked the guy that has to hump that thing around and shoot it what they would like to have? I spent 20 years in the army and was never asked what I thought about anything.
 
It's usually the skinniest guys in the platoon that get stuck with the M60 or M240. We make smaller targets than the linebacker sized guys do. And the gunner usually has it easy compared to his assistant gunner. The assistant has to cary the tripod, spare barrel, and extra ammo for the MG along with his own rifle and ammo load.
 
Tripods, extra barrel? Really? Sounds like the modern soldier has a lot of stuff to hump. Does everyone hump a 60mm round too?
 
Tripods, extra barrel? Really? Sounds like the modern soldier has a lot of stuff to hump. Does everyone hump a 60mm round too?

That is the way it was when I was in the Army from Jan 89 to Feb 96. I can't say about mortar shells since combat engineer units generally did not have any mortars.
 
That is the way it was when I was in the Army from Jan 89 to Feb 96. I can't say about mortar shells since combat engineer units generally did not have any mortars.

So there is a possibility that a grunt platoon would not hump a tripod and barrel. A short action .277 would be interesting. But then Winchesters short fat magnums didn't last long.
 
So there is a possibility that a grunt platoon would not hump a tripod and barrel. A short action .277 would be interesting. But then Winchesters short fat magnums didn't last long.

The assistant gunner will carry the spare barrel and extra ammo no matter what. I don't know of any light, medium, or heavy air cooled machine gun old or new that does not have to have the barrel changed after so many rounds fired. The new Sig 277 is basically the same size as the 308/7.62, just runs at a higher chamber pressure.
 
The assistant gunner will carry the spare barrel and extra ammo no matter what. I don't know of any light, medium, or heavy air cooled machine gun old or new that does not have to have the barrel changed after so many rounds fired. The new Sig 277 is basically the same size as the 308/7.62, just runs at a higher chamber pressure.
The a gunner carried ammo as did several riflemen. In a long action the M60 get a little warm but there were crazies who went out into the night and killed NVA with e tools to get their guns. Hopefully, things have improved.
 
Last night as I was dozing off I had images of cartridges and numbers floating around my little noggin.... It appeared to me that things have sort of come full circle in the last hundred years. Shortly after WWI both the US and Britain seemed to arrive at the conclusion that a .277 diameter bullet offered better ballistics than the .30 caliber cartridges then in service. Experiments with the 276 Pederson and 276 Enfield followed. They were still full length cartridges necked down to .277 diameter.For various reasons those cartridges were never adopted.

After WWII the British return to the smaller diameter bullet idea, and with battlefield experience with German and possibly Soviet ammunition, as well as the improvements in propellent, the cartridge can now be shorter. The shorter cartridge case was adopted by NATO but the .30 caliber bullet was retained only to be largely replaced by a .223 caliber cartridge. Most the intervening 50+/- years has been reviewed here and now the US is faced with the same fact that the powers that be were looking at 100 years ago.

In the interest of brevity I have left a lot out but I think that is the Reader's Digest version of things. Maybe I just should have gone to sleep....
 
From what I remember reading, the downfall for the 276 Pederson was the fact of all the 30-06 ammo held in stockpiles along with having to retool the gov. ammunition plants. Oh and that Gen. McArthur was against it. The .277 caliber bullets have proven themselves over and over again from the intermediate cartridge length - 6.8 SPC or in a short action length based off the 308 case or in long action such as the .270. In my opinion, if either the 276 Pederson or 276 Enfield round would have been adopted, we probably would have never saw the .223 caliber used for military rounds.
 
I would not be surprised if we simply end up with the same guns with new projectiles and propellants. They have already gone 55 to 62 to mid 70s for some applications. The proposed 6.5s under 2900 fps will not make the grade. You have to keep velocity to deal with commonality of armor, whether on people or vehicles. I suspect it's more likely we see 556x45 pushed with better multi-based powders that can run 85k with 75 to 80 grain penetrating bullet at 3300 to 3400 fps from the longer SAW barrels. Then it's simple swap out barrels/springs/buffers on older guns which are considered maintenance items anyway.
 
... In my opinion, if either the 276 Pederson or 276 Enfield round would have been adopted, we probably would have never saw the .223 caliber used for military rounds.

I think that big "What if...?" was coming into view about the time Sandman caught up with me.
 
Aw, hell, let's just put a 150 grain bullet in the built-for-strong M855 case and power it with 20 grains of pure nitro. Pressure be damned. And we should increase the twist to 2 inches. And the freebore to 12 inches. And the barrel length to 25 inches.

That seems to be the endpoint of the problem of making a .223 cartridge more effective.... amiright?

Jeeze. Fifty years of stupidity brought on by Colt's merchandising skill and a mill of grease money.

As I said before:
"So frankly I pretty much gave up following the military's fruitless pursuit of power in the .22 caliber range because every time I heard of another "improvement" over the original M193 cartridge I spewed coffee all over and just laughed and laughed and laughed...:rofl: "

I'm still laughing.

Terry
 
Last edited:
I'm actually crying over it.

Over 50 years of being saddled by a turd. Now it's a highly polished turd.

However there's too much money in the system to get a change.

What we need is a law that O-6 and above can't leave the military and take a job with any company that does more than $10,000,000 a year in business with the US Government.
 
You're off by 3 orders of magnitude. Should be $10,000 a year.

I'm laughing because nobody's shooting at me. I can see why you're crying.
 
Last edited:
the downfall for the 276 Pederson was the fact of all the 30-06 ammo held in stockpiles along with having to retool the gov. ammunition plants. Oh and that Gen. McArthur was against it.
MacArthur knew that MGs do more enemy damage than rifles. And, it was during the Depression, so the War Department was getting no new money for a second caliber of ammo.

Also, the specs for rifle ranges had already been passed to the New Deal relief agencies to get ranges built. But, those range fans were committed to M2 ball, the 7x51 needed about 50% more range fan for rifles.
And it was the Depression, and there was a ton of already produced ammo just sitting around.

That was the end of the .276pedersen. Ordnance Corps couldn't justify it; so CoSA was not going to be able to Justify it to the War Department.

And, the BAR would have been some serious medicine with a pistol grip and in 7x51. Even though that's no longer the TraDoc being argued.

The "sweet spot" is going to be around 7x40, even if labeled 6.8x40 or 280/40 or some such.
 
Status
Not open for further replies.
Back
Top