Gunsmithing timing PRI Brake on ar barrel.

[radmcg]

I have a Ar with a PRI MB on it It has been in the safe for a while. This is one of the few I bought assembled from MSTN if I recall. Just took it out and noticed the brake is 180 out of time. Took it off checked to make sure it was a crush washer and went to retighten it. It is way to tight to make it rotate 180 degrees. Can you squeeze a crush washer in a vise and then install it? Do I just need another crush washer or am I missing something.
AHA
Rad

 

[CS223]

Re: timing PRI Brake on ar barrel.

You could use a peel washer or a combination of the peel washer & crush aka Belleville washer to time it. Seems a little odd that you can't another half turn on it to time it up, you can generally wrench on it pretty hard if your barrel is held securely. Another option would be to surface grind a bit off the washer. If my math is right, removing 0.017" from the point of contact would give you 1/2 a turn on a 1/2-28 thread. Is the washer still concave? Might try a new crush washer just for grins.

 

[radmcg]

Re: timing PRI Brake on ar barrel.

Thanks CS. I really felt I was having to apply to much torque for my comfort so I went the grinding route. Timed up fine. I looked at the washer an it appearred to have pleanty of "crush" room. Not sure why it was so difficult to torque. Anyway I had already ground it down last night and it worked perfect.
Thanks
Rad