Thank you LRF, I have a lathe and do my own threading and chambering , didn't grow up around machine work or the equipment but in my adult life did buy some equipment needed because I hung around on Old time gunsmith anytime I had the time to spare, he was a real craftsman for the old world.
But I often wondered about the radius when listed on a contour or reamer drawing.
Like on the measurements you listed it states R-1 1/4 does that mean like a 1 .250 round disc would fit that radius when made correctly? some radius states, 1 1/2 or 5/8" or 1/2" . I have wondered about that?
Ron