Mr. Vicknair,
I join the others in thanking you both for your wonderful work in making an old gun right, and for taking the time to share your work with us. You're a true craftsman in every sense of the word, and it's a pleasure to view your work.
As a rank amateur, I can't help but wonder - how did you determine where to locate the drive-pin and vent holes? Everything lines up perfectly!
The bushing is torqued in place before it's cut from the raw stock. At that point I mark the horizontal centerline, then remove the bushing, cut it from the stock, square it and then mark the position of the drive pin holes. The holes are drilled, the bushing reinstalled and then it is filed flush to the breechface.
The vent screw slot is done in a similar fashion but is slotted instead of drilled. The actual vent is drilled in the lathe while the screw is still attached to the raw stock.
