.50 Remington Navy

The .50 Remington Navy / 13x21mmRF is a .50 in American rimfire handgun cartridge.

History
Introduced for the Remington Navy single-shot, rolling block pistol in 1865, the low-velocity round loaded a 290 gr bullet over 23 gr of black powder.

The rimfire version was replaced in 1866 by a centerfire equivalent. A Boxer-primed version remained commercially available until World War I.

The power of the .50 Remington was less than average, but the heavy bullet, even at comparatively low velocity, made it "a rather potent handgun round".