Manufactured from 1879 to 1887, the Model 320 Revolving Rifle is one of the rarest Smith & Wesson firearms produced, with a total production of 977. 224 were made with a 20 inch barrel; manufactured in three barrel lengths of 16, 18, and 20 inches with 20 being the rarest length. The 20 inch barrel has a globe front sight, two leaf rear sight, and two-line address/patent dates rib marking. Matching serial numbers are on the butt, cylinder, barrel and barrel latch. The forearm and grips are matching checkered mottled hard rubber. The detachable walnut stock features blued attaching hardware and hard rubber S&W buttplate.