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From the above article, anything 6.8 could be added to the next AWB, just as the wording " as powerful as a tank". Just can't own a tank and have it the hands of a common man.
 

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6.8 MM Ammo

I think it's great the Army has selected this caliber and I am ever hopeful that it will bring with it less expensive and more consistently performing ammunition. If it's all made to a standard spec, that would be great.
 

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Wow now the press says the 6.8 fires with the pressure of a Tank round.

https://www.foxnews.com/us/us-army-to-release-major-upgrades-to-decades-old-assault-rifles
That is not likely. Typical modern tank rounds operate at peak pressures of 69,600-70,325 psi. --- https://www.inetres.com/gp/military/cv/weapon/M256.html

More likely, and believable, is that the new 6.8mm round will operate at peak pressures in the 62,000-65,000 psi range of modern rifle and magnum rifle cartridges.

Consider that the current 5.56x45mm NATO cartridge operates at 55,114 psi (US Military SCATP) and the 7.62x51mm operates at 60,191 psi (NATO EPVAT) .
 

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Check military related sources not the fake news :)

The ballistics of projectiles between 6.5 and 7 were studied for wound characteristics, muzzle energy, downrange energy, and for some reason they picked the middle (or close to it).
Textron wanted the 6.5 I think.
I'm going to guess it will be a midweight 6.8 120 to 130gr, with a hardened penetrator, and in a case that won't remotely look like a Grendel or a SPC.
Look for a Biodegradable :) Polymer, bullet hiding TC.
They picked a diameter, weight and speed, nothing to do with what we shoot at paper or elk.
 

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@rocketvapor, kinda what I thought. Last I read, the military was looking at some type caseless ammo.(?)
Guess that would blow mil-surp ammo out of the water.
 

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Mil surp .30-06 is still around.
.223/5.56 has a big enough civilian following it will still be around.
Think we will be seeing penetrator 6.8 projectiles that we can use in our future?

The 6.8 Polymer Telescope Case is touted as saving weight.
A 130gr 6.8 cartridge weighs about 280 grains with 125gr of that being the primed brass case. For reference a 5.56 NATO 62gr cartridge is about 205grains.
How much lighter can a 130gr TC cartridge weigh? Several polymers are a lot lighter (1 g/cm[SUP]3[/SUP]) than brass (8.4 g/cm[SUP]3[/SUP]) and only have to last one shot but the thickness shown in sketches I've seen shows a good bit of plastic. Weigh a sharpie pen cap. 30 grains? So my guess is a weight savings for a 6.8 TC round to a brass 6.8 SPC round of less than 100 grains. Maybe 70 grains?
It adds up as that's a whole pound per hundred.
The hype about saving weight is mostly to shut down people saying the 6.8 round will be too heavy for little girl soldiers to carry :a32:

The 205 gr I stated for 5.56/62 is a little high. That is some foreign stuff I have. Our 62 grain cartridge is closer 190 grains.
 

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I'm not now, nor ever was a fan of mil surp ammo. I do like that mil surp, once fired brass, would be more available though.
Even punching paper, I'm not crazy about FMJ ammo. Call it OFS! (Old Fart Syndrome) ...but as a reloader, I always loved brass stamped "LC"! Whatever your goal with Lake City brass, it's good stuff!
 

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“The chamber pressure for the standard assault rifle is around 45 KSI [kilopound per square inch], but we’re looking for between 60 and 80 KSI … the chamber pressure when an M1 Abrams tank fires is on that order,” Norman told Task & Purpose.

Does sound like they are upping the chamber pressure.
While he says current is 45KPSI, isn't a high pressure cartridge more like 65KPSI now?
(SAAMI on the .300WM is 64KPSI, 22-250 is 65KPSI)
In order to do that you would need to eliminate the bolt lug design we now have in the AR-15. Sounds like a new (or really old) breech design to hold 80KPSI.
Maybe even a dual layer chamber.
Just think what you could with a 6.8/130 gr bullet with a 80KPSI chamber pressure.
Depleted uranium seems to have fallen out of favor for bullet cores.
Guess they will be stuck with steel or tungsten.
 

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The US Army has specified a particular armor-piercing 6.8mm bullet for its new squad arms. Its weight and intended velocity are not public info in order to confuse our geopolitical adversaries. Whether it weighs 100 grains or 120 grains, or something in-between, its fair to conclude it will have to be quite fast. Given the Army's stated need to be able to accurately strike and penetrate advanced personal armor at up to 600 meters (as I recall), a projectile long and pointy will be required, my guess is a 120 grainer at least. To drive a 120 grain 6.8 bullet at say 3200 fps will require a case much larger than our 6.8 SPC, something closer to the Ruger compact magnum or Remington's SAUM cartridges. Polymer cases are likely, telescoped ammo is not, IMO. Needless to say, recoil will be substantial enough to preclude full-auto fire from the new service rifle/carbine. Belt feed and quick barrel change are essential for the SAW replacement. I trust the Army's institutional memory hasn't forgotten the inherent shortcomings of the old BAR in that regard. I was there (early 60s) when the Army replaced both the BAR and the .30 cal MG with the then new M60 MG. Our troopers were glad to see the BAR go, but not the .30 caliber Browning MG. Personally, I thought the new M60 was the cat's meow. Loaded with a 200 round box of 4and1 it was as portable as the BAR and a deadly performer at the range (in peacetime anyway). - CW
 

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What if its a version of the 6.8 SPC's creator, some thing like this?

The 7.62×45mm case is also used as the parent case for a modified variant that is not officially registered with or sanctioned by the C.I.P. or its American equivalent, the SAAMI. Such cartridges which use commercial factory cases are generally known as wildcats. By changing the shape of standard factory cases (decreasing case taper and/or changing the shoulder geometry) the wildcatter generally increases the case capacity of the factory parent cartridge case, allowing more propellant to be used to generate higher velocities. Besides changing the shape and internal volume of the parent cartridge case, wildcatters also can change the original calibre. A reason to change the original calibre can be to comply with a minimal permitted calibre or bullet weight for the legal hunting of certain species of game or change external or terminal ballistic behavior. In his spare time Chis E. Murray has been developing a cartridge which he calls the 7×46mm Universal Intermediate Assault Cartridge.[7] The 7×46mm is designed to replace both the 5.56mm and 7.62mm NATO cartridges. It is low recoil and so can be used from carbines, but has long enough range to be used in machine guns and designated marksmen rifles. Its overall length has been optimized so that guns chambering it would be bigger than an AR-15 but smaller than an AR-10.

*Did Tacti-Wikiactical-Fu!*
 

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What if its a version of the 6.8 SPC's creator, some thing like [the 7x46 UIAC]?
Chris Murray also developed a 6.8mm version of the 7x46 UIAC, but the modest powder capacity makes it unlikely to be capable of delivering the desired performance.
 

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So when Mattis was named SECDEF, I was excited because I read that Marine Corps Times article on how he pushed for it behind the scenes. And then I thought, now that politicians are directing the movements based on political clout or money, it will come.

It did. It shouldn't just be our 6.8 SPC. That had its purpose, adapting the existing M4 at the armorer level with a better all around cartridge at longer distance. Make is specific like they are doing.

And I believe he has a lot to do with it.
 
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