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What is the story on the new cartridge being adopted by the military. I hear that it’s a 6.8mm.Thanks

I heard it was similar in size to the 308, but 6.8 (about 270). Guns are like 10 lbs. Don't know how well it will go over with the rank and file military. Seems to me they would adopt the 6.5 Grendal or 6.8 SPC to fit in existing rifles with only a barrel and bolt change. Grendal would offer range but probably fewer in a magazine. 6.8 might offer a few more in a magazine but limited to 200-300 yards. Grendal would go out to at least 600 yards.

Why change what works? 5.56 for 200 yards and under and for house to house fighting. .308 for longer range marksmen. Use both in a squad like WWII with 30-06's and 30 cal carbines. If they get overwhelmed, they always call in for air support or artillery.

To me the Grendal would offer the best of both. Harder hitting than 5.56, but not as hard or as long range as the 308.

The new military 6.8 operates at 80,000 PSI

Yep, because the case-head is steel.

It's pretty easy to Google all the particulars....

Mimics the 100 year old .270 WCF ballistics.

I looked up the SAAMI Sig 277 Fury spec and sure enough, the MAP is 80,000 PSI.

Oh, boy. Even though the spec warns don't go past 65,000 PSI, I can imagine some home rebarreling projects landing in the news...

Or else Sig limits their commercial ammo to 65,000 PSI...

ok. did a little googling: SigSaur is advertising ammo for the 277 Fury: 150gr polymer tip at 3120 fps, 24” bbl

any chance that rifles so chambered will be available to the public?

I thought they were putting them in the Sig Cross, but don't hold me to it ST.

I've never seen a 277 in the wild yet.

https://www.sigsauer.com/sig-cross-rifle.html

I've noticed the same thing - no gun availability. Funny thing is gun stores had ammo in stock like a year ago. Complete reversal from the usual gun first then ammo sometime situation.

Hmmm .. I think that would present some powder issues. I can't think of any current offerings that continue upwards in a predictable manner when pressure gets that high. Maybe there are, not sure. But I can see, with current powders, the possibility / probability of needing to stay around 65,000 PSI or below. Wonder if Mule Deer would chime in on this aspect?

Dunno. I'm not smart enough and experienced enough. However, for the near future I can picture Mr. Working Gunsmith and their liability insurer not touching this cartridge until more is known.

I'm still wondering if the Sig 277 Fury commercial ammo that you can order online today is spec'd at 65k or 80k PSI?

Does anyone else notice the irony of the new cartridge being in the same downrange performance family as the .276 Pederson and the British .280?

If you just use the brass-cased .277 Fury at normal pressures, it will be a great cartridge. Run it in a short action with a 3" magazine and seat to about 2.95" with a 23 inch barrel and load around 49 grains of H4350 and a 140 grain projectile. Velocity will be a touch over 3000 fps. Or you can neck it up to .308 and run 180's at 2750 in a 22 inch barrel using Varget with the same magazine set-up and C.O.A.L.

Why not just neck-up the 6.5 PRC? Personally, looks totally misplaced as a military cartridge, if they need more bullet, the 6.8 SPC looks good or even, brace yourself, the 6.5 CM (that would really put people up in arms, pun intended)!

Necking up the 6.5 PRC would also be good. But with the .277 Fury you're looking at 5 in an internal mag or 4 in some, with the wider PRC case 3 in most or with some modification 4. The 6.8 SPC doesn't just look good, it is good. You can use 7-08 brass and fireform it until the brass-cased .277 Fury brass becomes readily available.

My limited education on the matter says military cartridges need 1) performance, 2) mag capacity and 3) ease of manuf. (they gonna need a lot) Bullet weight counts for logistics too, a 100 lbs of 5.56 weighs 2.7lbs, 100 lbs of 7.62 weighs 5.25lbs, hence you can carry twice as much 5.56 as 7.62 ammo.

Maybe they should just neck down the .308 Win to .277 and call it the 270-08.. Nah,,

Yes, only yesterday I was able to fit 20 loaded SPC cases in an empty plastic bullet box (not much bigger than a match-box) to carry in my back-pack.

The .277 Fury case will hold around 4-5 more grains of powder with less case stretching.

I think if you were to read the military needs statement/project requirements many of the questions would be answered - among those would be individual cartridge size & weight. Big weight and space difference both in individual combat load and small unit logistics when comparing the 6.8 to much larger conventional 08/06-based & larger ammo; even more so when talking about high-rate squad-mg platforms. Ground operators are carrying heavier loads today than anytime else in US military history. I'm not blowing the horn for the 27-based new stuff just explaining some of the considerations that go into requirements definitions before bids are let. Weight & space capacity understandably remain a very important consideration here.