percucussion revolver

Looking to find any information on this rifle. I have been researching it on and off for weeks and really can’t find any accurate information on it other than the R.B. Stamp comes from a known maker. The gun is broken and does not shoot but I would like to know more about it before I hang it up...

I have a NMA with a cut-off barrel. It is serial numbered 140457 with all the Union acceptance proof marks. There's an additional serial number of "500" stamped on the bottom of the handle strap. The pistol looks to be used as a "fencing tool" during its' lifetime :) Surprisingly, the screws...