Hi I am wanting to put a bushmaster xm 177 flashider on my pre ban colt. Should I use a peel washer or a crushwasher to do this? Any info would help. You can email me at [email protected] if you dont want to post. Thanks JC

The washer you use would be dictated by the barrel and not the flash hider.  Use the same kind of washer you currently have.  If ya don't know what you have.  Remove the flash hider.  Look at the shoulder of the thread to barrel junction.  If it's undercut (concave), then it uses a crush washer.  If it's square, it uses a peel washer.  I could easily be wrong about this, but I think all flash hiders & muzzle brakes use a square cut on the end to be able to use either a crush or peel washer.

I hear crushwashers are the way to go. I used peel washers on mine and had to use 2 to get it indexed. So you might need to buy a few of each to get it just right.

Peel washers can be used.  Crush washers need to be used if your Flash Hider or Brake needs to be indexed.