Muzzle device timing

**Clyde777** · 04-09-18, 22:15

Hello, I installed a new bcm mod 0 muzzle device on one of my rifles and I used a new crush washer and when I was done it was a tiny bit off I would say more ocd off more than anything. Do I need to get a new crush washer and do it again or will it be okay?

**Grendelsnap** · 04-09-18, 22:58

Sounds like it's up to you. If it bothers you, crush washers are like $1.

**MistWolf** · 04-10-18, 00:36

Yes. If you over tighten the crush washer it will swage into the muzzle threads and be impossible to remove.

Ditch the crush washer and use shims instead.

**26 Inf** · 04-10-18, 09:07

The easiest way to time a device IMO is with different sized washers/shims:

Here is a commonly used set, generally good for several installs: https://precisionarmament.com/produc...washer-system/

This is a little different approach, but the price is much lower: https://www.joeboboutfitters.com/PWS...p/pws-shim.htm

You can also use peel washers to align, description here: https://www.whiteoakarmament.com/peel-washer.html

The advantages of the precision shims/washers over crush washers is that they require less torque to install and offer more precise alignment between the device and the bore, this is especially necessary if you are installing a device which hosts a suppressor.

**556Cliff** · 04-10-18, 14:41

Here is another option for crush washers. > https://armageddontactical.com/produ...achined-finish

These ones don't swage into the muzzle threads like mil-spec crush washers can, and they don't take unreasonable force tho crush either.

I don't know how these would do with suppressor alignment since I don't think anyone has ever done any testing with them.

**Clyde777** · 04-10-18, 14:43

Okay so the muzzle device is slightly off center on the loose side so can I just use my tool and tighten it a little so its lined up or should I get a new washer and redo the whole thing?

**556Cliff** · 04-10-18, 14:50

Originally Posted by Clyde777

Okay so the muzzle device is slightly off center on the loose side so can I just use my tool and tighten it a little so its lined up or should I get a new washer and redo the whole thing?

The spec for mil-spec crush washers is: 1/4 turn minimum to 1 1/4 turn maximum.

**MistWolf** · 04-10-18, 18:23

Originally Posted by Clyde777

Okay so the muzzle device is slightly off center on the loose side so can I just use my tool and tighten it a little so its lined up or should I get a new washer and redo the whole thing?

Yes, you can just tighten it a little more. If you go past, you'll need a new crush washer to satisfy your CDO.