The Ruger Hawkeye is a single-shot pistol chambered for the .256 Winchester Magnum cartridge, produced by Sturm, Ruger & Co. from 1963 until July 1964. It was built on the same frame as the Ruger Blackhawk, but rather than having a rotating cylinder like a standard revolver, it featured a swiveling breechblock which allowed an individual round to be loaded and sealed into the frame. The Ruger Hawkeye pistol was not a commercial success, and was discontinued after only 3,075 were produced. References External links Serial number history Instruction manual Sources Larry Kelly, J. D. Jones. Hunting for Handgunners. Book Sales, 1990. . Single-shot pistols Sturm, Ruger & Company Weapons and ammunition introduced in 1963