Anyone use Shims for Ops Inc Brake & Collar

[5RWill]

Was installing the brake and it stops on the crush washer with a full rotation and a fourth of a turn left. Ops Inc's max specs are no more than 450 degrees torque (i assume that would be approaching) but recommends 90 degrees (1/4th a turn). Problem is with the crush washer it lines up like this. With open face of the brake pointing up & down. So i guess i'm going to order shims?

 

[Nisils14]

is what you have now finger tight/snug or wrenched on completely? Make sure the upper is in a vice, and with a adjustable wrench turn the brake until the skinny part is at 12 c'clock.

 

[5RWill]

Finger tight/snug. The upper isn't in a proper vice like it should be i just locked in my tipton vice which probably isn't recommended. Though it wasn't difficult to get the A2 off. I know the skinny webbing is supposed to be at 12 O'clock but i would have to go a full rotation and a half to get it there.

 

[TexasGunTrustLawyer]

Stupid question.

Does ops inc use a crush washer?

We usually never use crush washers for suppressor mounts and I can't remember is ops inc is different.

 

[TexasGunTrustLawyer]

Did a search and found a few threads. Ops inc dies come with a crush washer, but it sometimes doesn't crush evenly.

So never mind

 

[mallrat]

Maybe try an old style tear-away washer. Or shim it to spec.

 

[5RWill]

Was thinking i'd order a surefire or PWS shim kit and stick a shim behind the crush washer? I could always let a smith take some off of the crush washer.

 

[Nisils14]

I think you should be okay with wrenching it down, from what I can see in the picture it looks like the skinny part is at 3 o'clock, so it should leave well within spec to get it to 12 o'clock. If anything try another crush washer. I was concerned as well with the ops inc brake using a crush washer, but I believe the tapered piece keeps their suppressor centered.

 

[5RWill]

Yeah i guess it wouldn't be an entire rotation. Would be a lot of torque though.

 

[5RWill]

Another question would this be okay to do in a Tipton gun vice? That's how I got the A2 off. Or should I just take it to a smith with a barrel vice or an actual vice and do it?


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[Nisils14]

Try it, maybe have another pair of hands to help hold it down. If that doesn't work, then get yourself an upper receiver block or have a gunsmith do it. either way.

upper block in Sporting Goods | eBay

 

[MSTN]

The depth of the threaded portion of the Ops-Inc 12th Model muzzle device is set up to be used with a crush washer. A stack of shims thick enough to properly time the muzzle device wont be as thick as a crush washer, and the threaded portion of the barrel will protrude slightly into the first chamber of the muzzle device.

Will the sky fall? No. But, it's just not the way things should be. The gun will run fine without a suppressor. But, it will screw up the proper spacing between the collar and the muzzle brake for mounting the suppressor. If you're actually going to use a 12th Model suppressor, the brake will end up too close to the collar and you won't get sufficient turns of thread engagement.

In the early days of the 12th Model, shims were used before crush washers were. And the depth of the internal threaded portion of the brake was commensurately longer.

I only use an adjustable wrench on the web of the 12th Model brake for the final quarter turn of tightening with the crush washer. I'll use an old A2 flash hider and a 3/4" wrench to get the crush washer very close to where I want it, first.

 

[5RWill]

I meant combining shims with the crush washer.

That's great idea of using the A2 to set the crush washer.


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