I am no help, but I would imagine .003” would probably fall within a tolerance for an o.d., but without a print and tolerance call out?What number are you trying to hit on your bore? What can your lathe hold? I like the idea of pound on Delrin brakes. Are you adding a set screw or just interference fit?Jason
I would like to order a muzzle brake for my HW95L, hopefully it will fit, but I will let you know.