NEW Military 6.8mm rifle

[TreyHouston]

So if the military goes to the 6.8mm bullet and rifle, will the 5.56 still be a “weapon of war”?

https://www.foxnews.com/tech/new-army-b ... er-hitting

Either way, I WANNA SHOOT IT!!!!

[ELB]

I've been reading and hearing that the Army is going to a 6.8mm cartridge with a new rifle and light mg to go with it, but I have yet to hear exactly what that rifle is going to be.

The linked article has this mystifier in it:

The Next Generation Squad Weapon will replace the M4A1 carbine for individual infantrymen. The Next Generation Squad Automatic Rifle will replace the M249 Squad Automatic Weapon, the “SAW.”

So everyone gets a Squad Automatic Weapon?

[jason812]

Was talking about this with a friend. Are they looking at the 6.8 SPC or something like the .277 Wolverine? Seems like a massive headache to get away from a 5.56 based case. New mags, bolts, and barrel extensions plus I dont know how easy it would be to change a SAW over to a larger bodied case.

[Noggin]

All this to get back close to a caliber that was available in the early 50's the .280

[MaduroBU]

Where does this stack up against a .224 Valkyrie (essentially a .220 Russian Improved) or a 6mm?

I'm working on a 7 62x40 WT to get more mass (using 150 grain FMJBT for practice and 150 gr SST for hunting). I am trying to kill man sized creatures (deer and hogs) at 50-200 yards, a task which has been ably accomplished by 150 grain bullets at 2200 FPS IMPACT velocity for 120 years. I want them to die quickly from heart shots because I want to eat them while their instincts all demand that they run as far and as fast as possible when confronted by pain or danger. I can carry 2 10 round magazines, which is overkill that I justify by saying that I might see some hogs and get off 3 or 4 good shots due to my can.

An Army or Marine rifleman or automatic rifleman has a very different problem. He has no interest in eating his opponent or even killing him. He merely wants to produce a casualty, which means that the shot opponent is no longer willing and/or able to continue to actively harm our rifleman or his friends. Killing the opponent, much less "anchoring" him via a "dead right there" shot, matter only in rare, up close fire fights. Further, this guy must carry 420 rounds on his person AND help carry ammo for the automatic rifleman. That equates to a standard 10kg load+automatic rifleman ammo+everything else, which rapidly adds up. Running out of ammo is perhaps the worst thing that can happen, as it can force soldiers and marines who are otherwise combat effective to immediately cease effective resistance.

The thing that you want is energy and sectional density on target(energy penetrates hard, thin barriers like armor; momentum penetrates deep, soft barriers like an angry buffalo). You also want your ammo to be as light as possible so that you don't run out. Finally, you want velocity within the confines of recoil and barrel length.

With that said, I wonder if a 100 grain 6mm bullet from a 7 62x39 sized improved case might be better (i.e. the 6mm PPC, 6mm AR, et c). To effectively use such a round, you'd need a 20-22" barrel, which necessitates a bullpup to meet length and weight requirements. The excellent SD would allow sufficent velocity to penetrate armor to 300 yards, assuming a good AP bullet. The reduced size of the round wouldn't lead to over burdening troops vs 62 grain 5.56x45.

Anyway, just some thoughts.

[jason812]

One of the articles I read mentioned looking into polymer cases to reduce weight. I don't see how they will be durable enough for war fighters.


Maduro, the .277 Wolverine is basically a 5.56 shortened and necked to use a 6.8 bullet (same diameter as .270 Winchester). It wont touch the Valkyrie but that round is in .22-250 class but it comes close to the 6.8 SPC without using different parts in an AR. Were you asking about 6mm Remington or 6x45? The Wolverine and 6x45 will both do about the same thing but you can get heavier .270 class bullets for the Wolverine. If all goes to plan, I will build a Wolverine chambered AR next year. I was going to build a 6x45 but changed my mind.

This is the advertised velocity for the Wolverine with a 16" barrel.
85 grain MPG - 2750fps
90 grain TNT - 2700fps
95 grain TTSX - 2600fps
100 grain Accubond - 2600fps
110 grain Sierra Pro-Hunter - 2500fps
110 grain Hornady V-Max - 2500fps

Of course all this is speculation as the only mentioned the bullet diameter and no other specs on velocity or what case it will use.

[howdy]

Rifles do kill a percentage of the enemy but the vast majority are killed by artillery, Naval gun fire and aerial bombardment. Ask the Iraqis in the first Gulf War what they feared.

[MaduroBU]

One of the articles I read mentioned looking into polymer cases to reduce weight. I don't see how they will be durable enough for war fighters.


Maduro, the .277 Wolverine is basically a 5.56 shortened and necked to use a 6.8 bullet (same diameter as .270 Winchester). It wont touch the Valkyrie but that round is in .22-250 class but it comes close to the 6.8 SPC without using different parts in an AR. Were you asking about 6mm Remington or 6x45? The Wolverine and 6x45 will both do about the same thing but you can get heavier .270 class bullets for the Wolverine. If all goes to plan, I will build a Wolverine chambered AR next year. I was going to build a 6x45 but changed my mind.

This is the advertised velocity for the Wolverine with a 16" barrel.
85 grain MPG - 2750fps
90 grain TNT - 2700fps
95 grain TTSX - 2600fps
100 grain Accubond - 2600fps
110 grain Sierra Pro-Hunter - 2500fps
110 grain Hornady V-Max - 2500fps

Of course all this is speculation as the only mentioned the bullet diameter and no other specs on velocity or what case it will use.

I was asking about 7.62x39 improved derivatives with the thought that this round was more like a 6.8 SPC than a .277 Wolverine. The big issue for the necked up 5.56x45 cases is bullet length within STANAG magazine OAL. This is the big reason that I went with a 7.62x40 WT: it's the biggest bullet that you can fit and still have a shoulder. I intend to try Hornady 220 grain RN loads, which may be quite good if they get close to the 1750 FPS that Quickload projects. That's not the problem that the military is trying to solve- they need the bullets to be longer so that they retain energy at range and have a higher SD for a given weight when they hit. a 5.56x45 derivative case neck location (i.e. to far forward for bigger bullets) means that you're limited to small bullets (e.g. 70 grain 6mm or 110 grain .277 bullets) unless you want to single load them (which is less than ideal in, say, an M249). The improved 7.62x39 based rounds solve that problem with with slightly reduced magazine capacity to put more powder behind the bullet.

The 6.8 SPC has a lot going for it, but it lacks standardization. With a 7.62x40, I can use .308 bullets and 5.56x45 cases- as long as people are reloading, those components will be available. The military can make its own standard via one phone call to Lake City (okay...years of meetings, proposals, GAO reports, pointless scandals....but they can do it). They still likely want to reuse what can be reused and avoid modifying the STANAG standard for magazines, which makes something like the 6.8 SPC even more useful if they can avoid bolt head reliability issues. My point is that a 6mm may get the same wounding (not incapacitation or lethality- just producing a casualty) potential at <300m for less weight. It seems like a 6mm might get us there as well.

I have seen the plastic case proposals, and that change would make bullet size MORE important, not less. Caseless or plastic cased ammo has a much higher proportion of its mass in the bullet, which means that a soldier can carry nearly 150% more 100 grain 6mm vs a 150 grain .277 (again assuming that we're holding impact velocity at 300m and SD constant).

WRT the barrel length issue- we need bullpups. My M17S wtih a 17.5" barrel is 26.5" vs an AR15 with a 11.5" barrel at 30.5" with the stock extended. If a rigid buffer tube behind the action were better than a recoil spring over the barrel, we'd see it more often. Instead, ONE rifle does it that way while all of the others, though most aren't bullpups, mount the spring above the action. As a result, AK pattern rifles can be fairly easily converted with kits, as can M1A1 rifles, et c. The M17S itself is an AR18 derivative, which shows where Stoner's thoughts moved after the AR10 and AR1 (i.e. to a op rod, like the rest of the world). Indeed, Stoner's AR18 gas system is likely his greatest contribution to the world of rifles, as it's popularity led it to show up in the service rifles of most nations not named America, Russia or France. It's not a crazy time to reconsider that idea ourselves.

Anyway, broad topic but very interesting.

[MaduroBU]

Rifles do kill a percentage of the enemy but the vast majority are killed by artillery, Naval gun fire and aerial bombardment. Ask the Iraqis in the first Gulf War what they feared.

Agree completely. It seems like the worry is that an armored enemy might make those means THE ONLY way to harm the enemy rather than the PREFERRED way. You bring up an interesting point: it's a lot easier to armor against shrapnel than rifle bullets. 7.62x51 lead and copper ball will pass through a 3A vest like butter. Rifle plates, even very expensive military boron plates, are heavy and don't cover that much of you. Armoring a soldier against airburst artillery is likely much easier (i.e. lighter and COOLER) than armoring him against a battle rifle. What does that mean for mortars? Going a step further, should soldiers wear rifle plates on their chests or 3A kevlar on their backs, butts, rear thighs, heads and shoulders?

The military may be concerned that in a war against a wealthy world power (which I'd rather not ponder), they don't want the M2 firing Silver or Black tips to be the only effective weapon man portable weapon.

[Liberty]

The search for the magic bullet is a neverending quest.

[cmgee67]

6.8 is a good choice but I wish they’d just go to 7.62x39 or 308

[bblhd672]

6.8 is a good choice but I wish they’d just go BACK to 7.62x39 or 308

Fixed it for ya!
Doubtless the military will spend billions on this before it’s settled and the soldiers/marines who have to carry them will look at the new thing and ask “who thought this would work for us?”

[howdy]

Lets see.....2,000,000 rifles X $3000/rifle (probably much more) is $6,000,000,000. Add ammo for training and front line units....unknown. Well, look at the good side. Maybe the M4's will end up at the CMP. There should never be a shortage of 556 ammo in our lifetime.

[G.A. Heath]

6.8 is a good choice but I wish they’d just go BACK to 7.62x39 or 308

Fixed it for ya!
Doubtless the military will spend billions on this before it’s settled and the soldiers/marines who have to carry them will look at the new thing and ask “who thought this would work for us?”

As far as I know the Army can't "just go BACK to 7.62x39" as it was never an officially issued cartridge as it was the official cartridge of the USSR. Some units have used it and the associated weapons but those were for specific operations. Going back to 7.62x51 is a possibility.

[Beiruty]

I read they are running after 6.5mm in AR10 frame. With 110gr Armor piercing projectile to defeat ceramic and coated light steel armor.