I have a Uberti 1861, a Pietta 1851, a Signature Series Pocket Navy and a Uberti 1860 which I assembled from a kit. All have arbor holes which are too deep to one degree or another. I put a plug in the bottom of the hole to take up the slack and make the bottom of the barrel even with the front of the frame. Mine came out OK, but if the cylinder-to-barrel gap ends up too large you might have to take some material off the barrel lug where it meets the frame. Be careful to keep it parallel to the original surface. Best to do it on a milling machine. There is a thread on "The Open Range" forum where the author drills a hole in the end of the arbor and puts a Dillon cartridge guide pin on to lengthen the arbor. I chose not to drill the arbor on the theory that the hole would reduce the area bearing on the wedge. Instead I drilled the bottom of the arbor hole and made a steel plug with a tang to go in the drilled hole. Either method will work and the difference is likely more theoretical than practical. L. O. G.