The barrel can be left alone. Changing the cylinder may be a simple matter of swapping them, but may also require fitting by shaping the hand or the ratchet notches to get the cylinder to lock up properly.
Timing is the potential problem you would be dealing with -- whether the interaction of the hand and ratchet would push the cylinder just far enough, without going too far, to allow the bolt to properly fall in to the notches in the cylinder. In many cases, the drop-in fit will be good, or very close. It then takes some careful study, patience, and a light hand with the file to get everything working in concert.
A forum community dedicated to Sport shooters, owners and enthusiasts. Come join the discussion about optics, hand casting bullets, hunting, gunsmithing, styles, reviews, accessories, classifieds, and more!