I have a new service 455 that was converted to 45ACP back in the day. I did not like to fool with the moon clips plus it was very inaccurate, which since the bore was near perfect I that I thought might be due in some part to the difference in bullet diameter. In any event I Bought a cylinder , from Mr Dunn on the board, and took it the the Smith. When checking things the cylinder is 4 thousands to long. Sooo ! we can trim the cylinder on the forcing cone end or trim the forcing cone. we decided to trim the cylinder. Was there this much variation back when this was made(1914) that there would be this much variation??