I recently got an Uberti Remington NMA with a case hardened frame. Beautiful revolver with a very small cylinder to barrel gap.
I found # 10 Remington caps fit much better than #11's. I was shooting a .454 Speer ball over a Wonderwad and a 30 gr Pyrodex pellet.
I put 36 rounds through it and it still wasn't binding up. The sights certainly are an improvement over the Colt 1860 and 51 Navy. The first 12 shots all went into a paper plate at 15 yards shooting duelist.
Pics of the NMA are straight from the range.
This revolver is a keeper!