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Suppressors Removing AAC Brake Shims

MadKap

Sergeant
Full Member
Minuteman
Jul 5, 2010
113
0
36
Hello,

I just picked up my thunderbeast 30p-1 and want to give it a go on my 700. Previously, I was using my SDN-6 and so I've had an AAC 51t Brake on there. I was able to remove the brake just fine, but the I cannot figure out how to remove the two indexing shims (see below). I've tried soaking the muzzle first in water and then in m-pro 7 for 24 hours and it hasn't helped a ton. I'm not sure if the pressure of having the muzzle brake screwed on has joined the shims to the muzzle shoulder, if rocksett just doesn't dissolve easily, or a combo of both.

9rmwqTX.jpg


Any tips on how I can remove these shims? (stainless steel colored rings there at the muzzle shoulder. Partially obscured by old rocksett (I think it's rocksett and not corrosion)).
 
I understand that hot water will dissolve Rocksett. The water that you used, was it hot?

Also, a heat gun, maybe?
 
Ah I didn't use hot water, I'll give that a go.

Tried to pry them with a small knife but couldn't get even the thinest part of the blade under them.
 
Vise grips of the proper size. Lock the shims in the vise grips (around the circumference) and twist. I think the shims will pop loose as soon as you start to squeeze them, but I'd be surprised if the shims stayed on for more than a little bit of torque.
 
Ah I didn't use hot water, I'll give that a go.

Tried to pry them with a small knife but couldn't get even the thinest part of the blade under them.

I'd be careful not to fuck up the muzzle, threads or shoulder. One slip with vice grips and you're looking at a new barrel (or cutting that one down).

I just removed a 51T off an FAL for Cerakoting. It was locked on there too, but water broke it down enough that it came off fairly easy. Note I took it off IMMEDIATELY after removing from the water; it was still wet. Clean well after.

Even after soaking, there was still plenty of Rocksett to clean off the threads, etc. Pick for that.

You could try a crappy knife blade, one you don't mind damaging, and see if you can tap that under the shims to work 'em loose. Just be careful. Good luck. Can't imagine you got the damn thing off but are having problems with shims! Go figure.
 
Shims look like stainless steel to me.

I'll see if I can use a thread protector to make sure things are safe before I do anything with tools and the shims.

Boiling water first though. Will update my progress friday or saturday.
 
Thanks everyone for the help. Submerged barrel tip in boiling water. I then used vice grips to squeeze the shims (extremely carefully). The shims were crushed and popped off!

I actually had 3 shims on there (I was super anal about indexing correctly and guess I needed 3 to get that last degree).
 
Thanks for starting this thread. I haven't taken any of my AAC brakes off yet, but now I know what to do if I have the same problem.