Muzzle brake shims not flat because barrel shoulder isn't square

[masakari]

Rifle is an LR300, so replacing the barrel is not an option.
Brake is 9mm 1/2/28, rifle is 5.56, can is Omega .300 (might get a 556K later)
Is this ok as is, or should I try to figure something else out?
It's tight and timed correctly. Rocksett is still drying.
Thanks

[lordmorgul]

Doesn’t cause any issues, cosmetic. I have similar on other rifle a few years.


Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!

[1168]

Does it have a false shoulder?

[masakari]

Does it have a false shoulder?

I think it's just a slightly rounded shoulder.

[masakari]

Doesn’t cause any issues, cosmetic. I have similar on other rifle a few years.


Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!

Thank you. That's what I'm thinking.

[MQ105]

Are you running a can? If so, check alignment. If not, no worries.

Many barrels do not have a relief cut behind the threads, and thus have a slightly larger diameter next to the shoulder. This requires a shim/spacer that is chamfered or slightly larger than what will fit over the threads. Several manufacturers include such a spacer (Surefire, for example). Without the oversized or chamfered spacer, shims will deform as they are pushed over the uncut area behind the threads.

reference: https://www.surefire.com/wp-content/...tion_Rev-C.pdf

[Clint]

Definitely check suppressor alignment with a rod.

Adding a beveled spacer or using a single thick shim washer such as the Precision Armament may work better in this case.

Rifle is an LR300, so replacing the barrel is not an option.
Brake is 9mm 1/2/28, rifle is 5.56, can is Omega .300 (might get a 556K later)
Is this ok as is, or should I try to figure something else out?
It's tight and timed correctly. Rocksett is still drying.
Thanks

[LMT/556]

The SureFire shim kit has a spacer designed to deal with this issue.

MQ105 already said it...