Sylvester H. Roper was a prolific inventor in the mid to late 19th century whose inventions included various steam bicycles and automobiles, the shotgun choke, and various firearms designs. In 1866 Roper designed a revolving shotgun with an exceptionally unique design. The action consisted of a series of fins which held the shells in a revolving mechanism, which had a capacity of four shells. The carrier was loaded through a hinged port at the top of the receiver, from which empty shells were also ejected. When the hammer was cocked, it pulled back the breechblock and ejected the empty shell while simultaneously rotating the carrier. When the trigger was pulled, the breechblock slammed forward, driving a new shell into the breech, then discharging it by depressing the firing pin.
The Roper revolving shotgun was produced from 1866 up until the mid 1870’s. Sylvester Roper died testing one of his motorcycle designs in 1896.