Now this is a neat piece, an original Confederate Griswold Barrel, Mounted on 1861 Colt Navy frame, the serial to 61 Navy half is 15095, it is on all parts, the cyl pin was screwed out about one turn, then the tip shortened, leaving  509, the last # five was removed, the cylinder has some built up patina only # visible is 5 , the wedge is # 5487, the barrel shows some twist in the surface no cryptic marks, Just the serial # in the low 400's , cryptic mark may have been under muzzle, may have ground off, one little spot looks for a relief on lever catch. The grips are well made with Griswold rake to them, has a good feel and points naturaly to your target