After the Civil War there was an abundance of Spencer rifles on the market. Some enterprising western dealers took advantage of the cheap prices and converted them to single shot Buffalo Rifles by installing heavy octagon barrels . These rifles would hold up to the heavy hard use required . This rifle was converted and sold by Schneider & Brownng – San Francisco , Cal. which is stamped on the heavy barrel. Don’t know what the P.A initials signify but could just be the owners initals. These early guns were the first in the trade and predated the 1874 Sharps and were used mostly in Kansas and Texas on the southern herd in the early 1870’s . This rifle actually surfaced in Texas. It’s got a great “been there, done that look”. The gun is 14 lbs. with a 28″ .46 cal. heavy octagon barrel. Two rifles sling loops were installed and the loading tub was eliminated as the gun was now a single shot.