Well the really primitive way would be.
1. Take the cylinder & crane out.
2. Using a fine cut file, evenly remove as much barrel shoulder as necessary to get the barrel screwed back tight in the frame with the front sight straight up & down.
3. File off straight & square enough barrel shank needed for the cylinder to go back in and leave the proper B/C gap.
4. Re-cut the forcing cone with a forcing cone reamer.
If you have an old barrel that was already fitted to a different gun, you may or may not have enough shoulder to tighten in the right place, or enough shank left to file though.
rc