Anybody here have an AR in 10mm Auto ?

[cwlongshot]

I have a 40AR and run a 308 carbine Spring and a 10oz buffer for heavy loads. Gas in my face is MUCH reduced from the std spring and 7.5oz buffer that was installed.



I'm not pushing this gun hard, (I know the limitations of a blow back) but warm, as I would like to take advantage of the ballistics capable form its longer barrel. I haven't really loaded many loading's yet. But some heavy (er) 800X and Blue Dot loads have been fine no case head expansion only chronographed one nice day.. nothing conclusive yet.

The tungsten buffer was a welcome addition. Recoil impulse changed allot too.

CW

[jreinke]

Look for CMMG to come out with one in the MKg Guard ARs.

[Ballistic Edge]

While I dont own a 10 mm AR, I have recently built 5 different pistol caliber AR's. A wildcat 45 win mag, a 45 acp, a 9mm, and 2 different 9mm win mag based wildcats. All are DI. All but 1 run with and without my cans. It would not be that hard, and really not much different than the early days of working with the blackout. Pressure is nowhere close to being a issue. Just look at the 223. 6.5 Grendel, 450 bushmaster etc all run at significantly higher pressure.

Without calculating, but just going on experience, a pistol length gas system on a 10 mm barrel will be close, you would have to play with gas port size, use a adjustable gas block, open the bolt slightly in a lathe. and the upper is ready. You would probably have to open the ejection port a slight amount. It would most likely run on a standard spring and buffer.

As to lower I really like my glock mag lower, If i was to do 1 or 2 over I would use that lower and build my 45 acp on it then could just swap uppers. Also by going DI you dont need any of the blow back ejector crap. Also on the glock mag lowers you do have to put a small cut in the bolt carrier to clear the mag. no big deal in the mill.

One caliber I would like to build is a AR in 357 sig.

And back to the 10, you could probably step on it if you wanted. I almost can pick up 100fps on the 9mm AR verses the same ammo in my G19. So right powder selection in a 16 inch barrel maybe cool.

Good luck have fun
phil

[golfindia]

So how do you feed from a glock mag with a DI bolt? I'm not able to picture the physics of how that's going to happen.... I thought that the Bazooka brothers were using some different feed method, like a modified 6.8 mag?

To circle back around on my prior question about 220g 10mm subsonics: I tested out some Extreme 220g plated bullets with 4.5, 5, and 5.5 grains of Unique, 8" barrel. My Lyman manual lists Unique as the lowest pressure powder for 200g hollow points, which is why I picked it. 4.5grains, at 1.24" OAL clocked right at 925 FPS with an ES of 22FPS 5 grains of Unique did about 970 FPS with an ES of 11FPS. 5.5g got right at 1000FPS, but It was pretty harsh. I will probably go with 4.5g, much easier on the gun and brass.

[Ballistic Edge]

My glock mag ar 9mm uses this quarter circle 10 lower. Here is a link to the large mag lower https://www.quartercircle10.com/product ... ished.html
If you look these use a different ejector as they are set up for blow back. If you go DI you dont need any of that. as all of the operation is handled by the bolt.

There is another vendor but cant remember the name of who makes glock mag lowers.
I can shoot you a pic if you like.

It operates just like any AR you have. But the bolt and carrier has to have a small cut on the bottom to clear the feed lips as the mag is a different shape than a standard AR mag. extraction and ejection is the same as GI bolt no changes except fitting to the new case.
As for the bolt it self the 223 case is .378 inches in dia. the 10 mm rim is .425 in in dia. so the dia of a standard bolt needs to be opened .048 inches. Which is slightly larger than a 6.8 spc bolt.

My 45 win mag, and 2 9mm win mag wild cats use GI mags, the 45acp I chose grease gun mag as I have a bunch of them.
good luck in your endeavor