text: The Colt 1851 Navy Revolver is a cap and ball revolver that was designed by Samuel Colt between 1847 and 1850. The six-round .36 caliber Navy revolver was much lighter than the contemporary Colt Dragoon Revolvers developed from the .44 Walker Colt revolvers of 1847, which, given their size and weight, were generally carried in saddle holsters. It is an enlarged version of the .31 caliber Colt Pocket Percussion Revolvers, that evolved from the earlier Baby Dragoon and, like them, is a mechanically improved and simplified descendant of the 1836 Paterson revolver. As the factory designation implied, the Navy revolver was suitably sized for carrying in a belt holster. It became very popular in North America at the time of Western expansion. Colt's aggressive promotions distributed the Navy and his other revolvers across Europe, Asia, and Africa. The .36 caliber (.375–.380 inch) round lead ball weighs 80 grains and, at a velocity of 1,000 feet per second, is comparable to the modern .380 pistol cartridge in power. Loads consist of loose powder and ball or bullet, metallic foil cartridges (early), and combustible paper cartridges (Civil War era), all combinations being ignited by a fulminate percussion cap applied to the nipples at the rear of the chamber.