Thread: Machinist/Gunsmiths Muzzle Threading Query

As a machinist and gunsmith Im with Mimms2 on this. Always have a relief cut and a shoulder.

I normally get stuff like this in my shop when the owner or new owner wants to fit a new/another muzzle device and cannot get it to thread on all the way up to the shoulder. I always remind myself to cut the thread not for a specific attachment.

I've had barrels in my shop where the thread ends with a 45 or 60° shoulder. The silencer manufacturer was of the opinion that a taper is supposed to assist with alignment....which it did'nt - a flat shoulder to bottom out against would have been better.