44 S&W. This, then, became the Single Action Army, a gun that would signal the end of the Open Top. Within months, the .45 Colt SAA was readied and re-submitted to the Army for testing.

Of Colt's Model 1877 double-action revolvers, the Lightning is the most well-known, chambered for the .38 Colt cartridge.

The Colt Single Action Army revolver, introduced in 1873, became a symbol of power and American expansion, used by both outlaws and lawmen on the frontier.