Since the questioner doesn't seem to know a lot about these conversions we should probably clear a few things up for his consideration. First, if he is going to convert it and dedicate it solely to firing cartridges he should consider sleeving the barrel. Sure you can buy healed or hollowbase bullets but the healed bullets are very hard to find (one guy in East Jesus, Texas, selling them doesn't make them easy to come by) and the hollowbase takes a soft alloy and/or a good charge to expand the skirt and seal the bore. Also, there are two kinds of kits. One has a bored through cylinder and is intended to be used with healed or hollowbase bullets and the standard .375 barrel. The other has a standard stepped chamber and is made to use with .357 bullets and a .357 barrel. If you have the first type of cylinder, the one that is bored through, sleeving is a waste of time as you still can't use regular ammo since the bullet is so severely undersized for the cylinder throat. Bottom line is it is cheaper and you wind up with all the dimensions correct if you just buy a factory conversion. If you already have the guns and want to convert, just make sure you buy the right parts.