Hi, all recent BP revolvers made by Uberti have a short arbor. All recent Pietta BP revolvers (other than the Paterson) have a correct length arbor. One may ask why a correct length arbor is important? Take a new Uberti revolver and begin hammering in the wedge. Notice that the cylinder to barrel gap changes as the wedge is hammered in. Hammer enough and the gap disappears to where the cylinder is prevented from rotating. If one is interested in reproducible accuracy, the revolver gap must be held fixed. Remove the barrel and reinstall it and you have a new poi compared to the poi before. Also, the gap can change while shooting.
If you are serious about reproducible accuracy, the Uberti short arbor issue must be fixed. One way to do this is send your revolver to Goon's. There are a number of other paths to resolve the short arbor. Some drill a hole in the end of the arbor and insert a Dillon Precision index button. The button is then filed down to produce the desired gap. In the past I have solved this issue by JB Weld a brass button to the end of the arbor and filing down the button to produce the correct gap. A weakness to my past system is that is easy to over file the button. Then one must start over. Another issue is that if I want to increase the gap, I need to start over with a longer button. Of course there are probably another dozen methods to repair a short arbor.
I have recently taken another path. The short arbor end is drilled and tapped to insert a 10-32 set screw. The set screw is turned in to produce the desired gap. The set screw has a blob of nylon on the threads that keeps the screw locked in position. An advantage of the set screw is that the gap can be easily changed if ever desired. One gap for BP and another for smokeless with conversion cylinders. If happy with the gap set, adding a drop of loctite ensures it doesn't move with time. Over the last day I have replaced nine of my epoxy on brass buttons with set screws. I still have another seven Uberti revolvers to do. The photos below is a Uberti 1862 with arbor lengthening set screw attached.
Regards,
Richard