Monday, November 27, 2023

Two new- well, one new and one not quite new- cartridges,

one I'd not heard of before: 6.8SPC and .277 Sig Fury.  Hard to try to keep up at times.

The military version .277, pressure of 80,000psi.  Damn.  I wonder what that translates into in bolt and barrel life?

7 comments:

RHT447 said...

To say nothing of needing a "hybrid" case. All that wear and tear has to go somewhere.

Once again a military attempts to bend the laws of physics to come up with the latest Wunder Weapon. Don't get me wrong, I'm all for the latest and greatest tech for the troops. That said, their equipment needs to be 1) rugged 2)simple 3)easy to maintain 4) have a dependable logistics train. Remaining resources need to go into training and tactics.

Bona fides--Graduated Small Arms Repair School at Aberdeen Proving Grounds in '74. Was in the field during REFORGER '75 and '76.

Sailorcurt said...

I've got a rifle in 6.8spc. Was originally intended for use in SBRs because the bullet retains more energy over distance than 5.56. It was designed for the military during one of their "we need something bigger than this poodle shooter round" phases but was never widely adopted.

I built a rifle in that caliber with the idea that it's better suited for deer and medium game than 5.56, but has better ballistics than .300 blackout or some of the other bigger options. I've actually never hunted with it (yet) but I'm pretty sure it will do the job.

I think the new .277 cartridge was also developed for the Army...it uses a composite case that uses a lot of plastic to save weight, and is the latest iteration of the search for something with more oomph than the poodle shooter. With those kinds of pressures, I'd guess they're getting close to (if not matching) the velocity of .270 Winchester with that round.

I agree with you about concerns with barrel life. I'd think they'd be able to mitigate some of the wear on the bolt by adjusting the gas system and/or recoil spring, but that might be an issue as well.

MrHappy said...

I would assume a brass and stainless cartridge would not lend itself well for reloading.

Anonymous said...

…ehhh.
From a 75th ranger Regiment Sniper.
“Not 1 back up from the Winmag.”

Anonymous said...

That logistics train is going to derail 1/4 of the way through this 80k psi mess! Barrels will fry, bolts will be toast and SIG makes a buttload of money modifying the whole mess to reasonable standards.

Firehand said...

Which would mean replaying the Brit mess with the SA-80

Sailorcurt said...

I know this post is over a month old, I had just stumbled across the bookmark (I saved it in a different place than I normally do blog links) and looked at it again.

I never actually clicked the link the first time around...I was in a hurry and formulated my comment based on my memory...so I looked at the article you linked to.

First, why the heck were they comparing an Assault Rifle (AR-15 pattern) round with a Battle Rifle (AR-10 pattern) round? Assault rifles are, by definition, completely different animals, created with different goals in mind, than battle rifles. With the ability to chamber longer cartridges, of course the AR-10 pattern round is going to be superior to the AR-15 pattern. They should have compared the .277 Fury with .308 Win or 6.5 Creedmore.

The second thing I noticed is whenever they talked about bullet drop they'd say something like "zero drop at 100 yards..." Um...what was the rifle zeroed at? 100 yards? Hence the zero drop at that range? Made it sound like they simply didn't understand the stats they were talking about.

Finally: I didn't know what I was talking about. I thought the .277 Sig Fury you mentioned was that 6.8 composite cartridge round the Army was evaluating a few years back that had a steel base and a plastic body. Apparently the Sig cartridge with a brass body was a competitor in the same evaluation and won out over the plastic body version. My bad on that one.