Can anyone confirm if the crush washers supplied with the 1/2x28 and the 5/8x24 muzzle brake (the only ones that actually need to be timed) are actually the same crush washer?

I mounted the 1/2x28 brake on my LMT and messed up the crush washer when I was timing the brake tip. It's not badly messed up, but I can't get it on there tight enough that it doesn't start to walk after 50 or so rounds with the can on.

So I ordered 5 new crush washers from SIG customer service and they sent me, I suppose logically, ones that are specifically labeled 5/8x24.

I don't have another 1/2x28 adapter around to compare the crush washers for the two different brake tips.

Can anyone tell me if they're the same, or do I need to order again?

Not to answer your question directly, and I’m not familiar with your specific setup, but is installation of the “can” you reference specifically approved for use with a crush washer? The reason I ask is that Thunder Beast that I’m familiar with specifically cautions against using crush washers, presumably because of the possibility of misalignment, or perhaps for some other reason due to the suppressor’s weight.

Yep, I know Silencerco states to NOT use crush washers as well. Sigh could be different, but I would check your mounting instructions to be safe.

Yes, there is a crush washer needed for the muzzle brake tip of the QD adapter.

The SRD QD adapter itself doesn't use a crush washer interfacing with the barrel, but the muzzle brake tip (which can be swapped out for an untimed flash hider tip) comes with a washer to time it.

Suffice it to say, SIG ships with a crush washer in the package and tells you to use it in the instruction manual.

quote:

Originally posted by Oat_Action_Man:
Suffice it to say, SIG ships with a crush washer in the package and tells you to use it in the instruction manual.

Thanks.

I always thought shims were to be used for timing QD brake mounts. So I've always used them & used crush washer for non suppressor QD devices. (A2 or whatever...)