Is a crush washer necessary?

[tommag]

I bought one of the 16" grendel bbls from numrich and got a flash hider to fit the threads. It's the old style with slots cut all around. Us there a purpose to crush washers other than getting the flash hider in with the non slotted side on the bottom? I don't know if I need one with this style.
Thanks in advance.

[LRRPF52]

You can use either a crush or precision shims.

It depends on the thread length of the muzzle and the device.

If it bottoms out without the internal wall hitting the muzzle, then you don't really need a washer of any kind.

If it does bottom out inside before the device touches the shoulder of the muzzle, then use a washer.

I personally use zero/minimal torque nowadays, to eliminate any stress on the threads.

[tommag]

Thanks. It bottoms out on the muzzle. Looks like I need to use a washer.

[Klem]

The original A1 flash eliminator with vents all round (the one you have) uses a split washer.

Crush washers are one-time use only and were introduced to time the A2 eliminator. Split washers are better because you only have to do them up hand tight which means you can access the barrel crown for cleaning as many times as you like.

Brownells sells them for a couple of bucks each. You only need one.

[Retro]

I have compensator that I bought on Ebay and it came with a jam nut instead of a crush washer so there are several options available. http://www.ebay.com/itm/Rifle-Muzzle...QAAOSwXeJXfs85

[mongoosesnipe]

lately may go to has been precision washers and rock set