Colt 1851 Navy Revolver.

designed by Samuel Colt between 1847 and 1850. Colt first called this Revolver the Ranger model; but the designation Navy quickly took over.

After the Civil War, revolvers using fixed metallic cartridges came into widespread use. The Colt Navy remained in production until 1873, being replaced in the Colt line with what would become one of the manufacturer's most famous handguns, the Colt Single Action Army (also known as the Peacemaker and Colt 45).