This is a very hard pistol to find and actually only the 3rd one I've seen in 35 years.  It's one of the 1869-70 St. Louis Board trial pistols which was convened in order to pick a cartridge replacement for the percussion pistols the U.S Army had been using since the Civil War.  These trial pistols were to be supplied to the Western Cavalry units where they would be put to hard service.  The trials lasted for over 2 years and the winner in the end was Colt who ended up with the Govt. contract to equip the 10 Cavalry units.  The Remington trial guns all have the second set of numbers as this one does.  It has the number 38 on the barrel ,rammer, frame and the frame conversion plate.  This information on the U.S Trial pistols is found on page 54 of " A Study of the Colt Conversion and other percussion pistols" by Bruce McDowell.  The pistol functions very well and locks up tight.  A most for the Military or Western Collector. 

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