M28-2 Head Clearance, Recessed cylinder, vs current cylinder, hammer nose protrusion?
Just installed a new hammer nose in a M28-2 . Pin protrusion is about .048"
Question- Is headspace/head clearance the same for both types of cylinders.
Is the distance from recessed cylinder to primer the same for both types of cylinders?
Actually the maximum rim thickness is .060. The correct head space from where front face of rim rides to recoil shield is .060 to .074. A actual .060 rim would be rare. That is why a high primer can drag, say a .057 rim and a primer that is .006 high in a gun with .062 headspace and you get a bind. With your gun and a firing pin protrusion of .048 even with a max of .074 headspace and a thin .050 rim to give you total gap of .024 (this would be max tolerance stacking) you would still have .024 of hammer nose to dent a flush primer and .02 if the primer was pressed .004 low. In other ward BANG. But no you don't want max or min head space recessed or non.
I have put recessed cylinders in non recessed N frames and K frames with no problem other than normal fitting and you need to carefully file back the frame lug at the lower rear of cylinder window so the extra rearward length will clearance. I use a fairly fine file with one side safed (teeth removed) and some duct tape on the rest of the nearby frame. Jut did it yesterday day in fact, fitting a K22 cylinder that I had reamed to 327 federal in one of the J&G gunsmith special frames. Adjust the barrel extension for a nice cylinder gap, ream the forcing cone and add a front sight and I will have a 3 1/4: fixed sight 327 Federal. Another one I fitted a recessed nickel 357 cylinder and barrel to to make a fake Pinto model 13. Had to file back that lug too of course.
Last edited by steelslaver; 11-29-2020 at 10:11 AM.