This is a very interesting S&W .44 caliber Double Action Revolver in caliber .44 Russian with 1-7/16" cylinder. For starters, it has a low serial number in the 500 range which is 1st year production. It letters in the Smith and Wesson records as shipping from the factory on July 25, 1881 to M.W. Robinson (S&W's distributor in NY) with a 5" barrel. It was originally a blued finish gun as there are traces of original blue still visible in protected areas. The grips are mother of pearl. The left side of the frame is marked with the letters "RM" which is generally regarded as a property mark for the "Republic of Mexico". Over the years, we've seen "RM" marked Model 1866 Winchester Saddle Ring carbines, 1875 Remington revolvers, and even surplus Civil War musket lockplates with this marking. They are usually encountered with a small round stamp of a sombrero next to the RM, however, this one is just a plain "RM". The wear and hard use this revolver has seen is generally on par with other Republic of Mexico marked guns.
Overall condition grades to NRA Antique Good+ with the metal well worn and turned to a smooth light silvery gray patina with small traces of original blue around the barrel hinge, rear sight, and recoil shield. Hammer also shows a small area of faded original case colors. Numbers are all matching. See photos. Pearl grips are in very good condition with no cracks, missing chips, and fit very well to the metal straps. Judging from their appearance and fit to the gun, they appear to have been on the gun since new. The mechanics are very good shape with everything working nicely in both double and single action modes. Cylinder still indexes, lines up, and locks to the bolt. Barrel still latches very well to the frame. Good+ bore with strong lands and grooves. A little frosty but no signs of any major corrosion. No rings or bulges. A well used but solid example of an early S&W 44 CAL DA with a fantastic serial number, Republic of Mexico marks, and a nice set of pearl grips.