Congratulations on the mill. Fun stuff. I made a 1911 firing pin stop out of
416 SS to get one with the small radius I wanted. At that time some years ago,
SS ones with a square bottom were not available commercially. So I made one,
and tightly fitted it to my particular FP slot and extractor.
Small and not too difficult project, actually. All sorts of silly little things that you
need or just want.
Oh, yeah, and you actually FOUND a 1/2-27 tap? Holy cow. Where in the world
did you locate that, a "Unicorns 'R-Us"?
Bill