Mostly original Remington .44 military contract Civil War revolver that somebody must have decided they wanted to shoot (several decades ago). They replaced the front sight, trigger, grips and some internal parts and then had it professionally refinished (hot tank blued). The action and timing is near flawless and no doubt it would be a great shooter (but we don’t warrant antique arms to fire or be safe to use). The bore, likewise, is very nice so if you ever wanted to fire one of these original hand cannons, it would be a great choice. Unfortunately, as with most refinishes, they obliterated the top barrel marking.
The serial number below the barrel and on the left side of the lower grip frame match and military subinspector marks verify it was indeed military issue.
The number places it in the ranges of revolvers issued circa 1864 to the 8th Michigan Cavalry and the 6th US Cavalry (US Volunteers), according to Springfield Research Services database.