In 1871, Springfield Armory converted approximately 1,108 Burnside-Spencer carbines by fitting the actions with rifle length barrels chambered for .50 rimfire ammunition with three-groove rifling and adding the Stabler cut-off device. The armory also refurbished the parts and added a nearly full length forearm with two barrel bands and a slotted cleaning rod. Spencers were easily among the most advanced weapons of the Civil War and remained in use during the late-19th century Indian Wars in the hands of both the U.S. Army and various Native Americans. The left side of the stock, just behind the saddle ring base, is marked with an oval script "ESA" (partially struck) inspection cartouche of Springfield Master Armorer Erskine S. Allin, and the other components have the standard Burnside and armory markings. Matching serial number "24919" marked on the left breech end of the arsenal replacement barrel and top rear of the frame. It has a blade front sight doubling as a bayonet lug and notch and folding ladder rear sights.

Very fine as arsenal refurbished, retaining 75% plus bright arsenal blue finish on the barrel with some areas of light surface corrosion, a few light scratches, and scattered light freckling. 80% vivid refurbished case colors remain with a few areas of smooth brown patina. Wood is also very fine with defined edges, scattered scratches and dents, and a few mild cracks on either side of the butt. Mechanically excellent.