Wow, this is an old thread....What is wrong with 38, I know they handle differently than the 44s due ti barrel weight but it costs alot less too make BP 38 rounds, cheaper brass, bullets, and less powder, plus they recoil less allowing faster accurate shooting...
I have a couple of the ASM Richards in the 3000 s/n range, bought one 1860 new and the other right off this board maybe 10 years ago, both in 38. The one I bought new functioned very good but needed work to shoot POA, firing pin too sharp and also to handle BP rounds. The used one was worked on by a kitchen table gunsmith and it took a bunch of work to get it right, Uberti parts can be made too work in the action but you are on your own for the larger parts. They never shoot BP good the way they came but I added a collar to the front of the cylinders like you see on the Cimaron open tops and each of mine will shoot 50+ rounds of BP with no loss of acccuracy and the cylinder turns freely.
They are my Go-to guns, the 72 opentop is a close second, the RMs just don't do it for me.