I'm getting a brake put on my 6mm tomorrow (FINALLY!) but I don't know the thread twist/pitch, whatever it's called. Can anyone help? It's a SSG Vaporizer brake.
Most popular is 1/2" x 28 threads to the inch.
Dave was right on with his comment. If the installer can't figure the thread pitch out don't let him near your rifle.
The important part, IF the brake doesn't have openings all the way around, (side ports only) is indexing the barrel so that the ports are exactly perpendicular to the plane of the rifle.
I have one that is ever so slightly slanted. It makes no difference in shooting but it flat drives me nuts (I heard they have pills for thatlightbulb)