Aero Precison AR10 issue

[bamban]

You should have PLENTY gas pressure to cycle with the suppressor on!
Normally the adjustable block is to cut down to tame the violent pressure created with suppressor.
If not fired with original gas block… you could have an obstructed gas port or insufficient gas port size on the barrel or as mentioned before, misalignment of gas block to port.
If it cycles smoothly and locks into battery by hand then it it's definitely a gas issue.

Try another brand of ammo while you're at it just to eliminate an ammo issue.

I've built many of them and fixed many with gas issues. Even AR's from mass produced manufacturing have low end defective components .
I've had to bore gas ports on barrels, drill out obstructed gas blocks and tubes as well as properly align gas blocks.
You should also soak the bolt with oil and work the bolt back and forth in the carrier when new to "wear-in" .
Run it wet!

Agreed.

I've chambered over 150 AR barrels from blanks for competition the last couple of years or so, I even have to ask sometime what powder they use. For example AR Comp pressure curve is different from the more common ones..the standard gas port we use tends to have lock back issues. AR Comp needs a slightly larger port. Service rifle legal guns can't have adjustable gas blocks.

Someone mentioned about some gas blocks don't need to be against the shoulder. Gas block ports centerline tend to be anywhere from .275 to .300 from the edge. I drill/ream the gas ports .300 from the shoulder and cut a pad with a .125 end mill 180 from the port. Some gas blocks you can align by centering a cut-out when they drill the port to the pad.

 

[Darryle]

I rarely use an adjustable gas block, I tune using a heavy buffer and heavier spring. Why restrict the one thing that the rifle needs to properly function.

Pull the buffer and spring out, replace the buffer, with the upper removed, place the BCG on the lower and push it back into the buffer tube, measure between the bolt catch and the face of the bolt, you should have 5/16" - 3/8" between the two.

If you don't, measure the buffer length, measure the buffer spring length, these vary from their smaller AR-15 counterparts.

I am assuming it has a carbine butt stock/buffer setup. Measure the internal buffer tube depth from the retainer pin, the 308 is deeper, I don't have my cheat sheet in front of me, for the exact depths.

Understanding 308 AR buffer system

The AR10 uses a shorter buffer, lighter too, like 3oz. I run a 5.8oz buffer in one 308 and nearly 8oz in the 6.5 Creedmoor AR.

If you get the correct distance between the face of the catch and the bolt, your cyclic rate is too fast and your rifle isn't capable of keeping up, the catch or magazine isn't fast enough to push the catch or ammo up into the path of the BCG before it has passed.

 

[FEENIX]

Agreed.

I've chambered over 150 AR barrels from blanks for competition the last couple of years or so, I even have to ask sometime what powder they use. For example AR Comp pressure curve is different from the more common ones..the standard gas port we use tends to have lock back issues. AR Comp needs a slightly larger port. Service rifle legal guns can't have adjustable gas blocks.

Someone mentioned about some gas blocks don't need to be against the shoulder. Gas block ports centerline tend to be anywhere from .275 to .300 from the edge. I drill/ream the gas ports .300 from the shoulder and cut a pad with a .125 end mill 180 from the port. Some gas blocks you can align by centering a cut-out when they drill the port to the pad.

Brother, in my book, that makes you an expert, unlike me.

 

[bamban]

Brother, in my book, that makes you an expert, unlike me.

Far from it, bro. Just hacking at it

 

[ARlife4me]

What about the "adjustable gas brake". What the hell is that! Hopefully a typo! @bamban states about powder it's true on so many levels! Using fastest possible powder depending on barrel length can short stroke, completely act like a BA and/or leave you thoughtless. I have built many using AP products and all without issues. 308 is like 5.56 in AR's, you don't need an adjustable gb when using full mass bcg and standard buffer weights. Tuning for suppressors, specific handloads and/or cyclic weight changes, then yes it's useful having an agb. 308's and 5.56 are easy peasy unlike other variants in either platforms. Some get the gas port size right on the money without adding +2 and still use non-agb or heavy buffers so the primers don't pop out (even with factory ammo). I will tell you this! Unless stated for AR's the end product has been BA tuned/tested and that's why most 6.5creeds will pop primers with improper gas ports and unnecessary + lengths. I own many, so I know the issues and fixes.