BE SURE to check every dimension, especially the lock up groove. I had a Lyman 1858 that was built in the early 70's by Uberti. I bought a couple of NOS cylinders off ebay to make shooting a little more expedient. Both of the cylinders I had to fit lengthwise, which I was expecting, but what I wasn't expecting was that the cylinder lockup groove was NARROWER on one of the cylinders, which did not provide a whole lot of meat to be doing the locking up. I think Pietta has a reputation for being on the small side with their arms. Since your pistol is a Uberti, I would make sure that it was a Uberti cylinder. Or at least measure the lockup notch on a prospective cylinder, as it is pretty important.