This specific cartridge is a rimmed, straight-walled handgun round developed by Union Metallic Cartridge Company in 1872 for the Colt Single Action Army revolver. It quickly gained popularity and became a staple in the American West, used by law enforcement, outlaws, and civilians alike. Its dimensions are well-established: a .452-inch diameter bullet propelled by black powder, later smokeless powder, in a case just over 1.28 inches long.
The cartridges widespread adoption stemmed from its considerable stopping power and relatively simple mechanism. Its effectiveness at close range solidified its legendary status in American firearm history. Although later handgun cartridges offered improvements in velocity and other aspects, this classic round continues to be manufactured and used by enthusiasts for Cowboy Action Shooting and hunting, testament to its enduring design. Its impact on firearm development remains undeniable.