This is an example of a Spencer Model 1865 carbine that has been modified to rifle configuration by replacing the barrel with a heavy octagon barrel which is marked "A.J. PLATE/SAN FRANCISCO CAL" on the top flat behind the sporting type rear sight. The forearm as been shortened with a copper nose cap and a copper plate added with a sling swivel (which has a collectors tag attached), and the sling bar and ring have been removed. These modifications were probably done by a Western Gunsmith. The top of the receiver is marked "MODEL/1865" ahead of the standard four line Spencer/Burnside marking and the serial number is marked on the top of the frame directly behind the hammer. The caliber is uncertain but appears to take a long rimfire cartridge and gauges at 45 caliber. The receiver, stock, hammer and loading lever are unmodified.