Flintlocke
Im old machinist too. I figure the button would compare the same as a cut tap and a thread former with the roll thread being smoother
Now can someone buy two identicsl rifles and compare barrel breakin procedure with just shooting it?
You make a valid point. I don't know anything about formed threading but I imagine it is a somewhat gradual process. I put in a few days with old Chick Donnelly barrelmaker, in his shop and the buttons he used were very short, not much longer than the bearing surface of a comparable bullet. Anyway, it's all speculation on my part except for one time I was bored and cut a small section of new , cut rifled bbl lengthwise and I was impressed with the finish. Unfortunately only at 10X and I didn't compare it with anything else.
