The Colt Single Action Army, also known as the Single Action Army, SAA, Model P, Peacemaker, M1873, and Colt .45, is a single-action revolver with a revolving cylinder holding six metallic cartridges. It was designed for the U.S. government service revolver trials of 1872 by Colt's Patent Firearms Manufacturing Company known today as Colt's Manufacturing Company and was adopted as the standard military service revolver until 1892.
The Colt SAA has been offered in over 30 different calibers and various barrel lengths, but its overall appearance has remained consistent since 1873. Colt has discontinued its production twice, and twice brought it back due to popular demand. The revolver was popular with ranchers, lawmen, and outlaws alike, but as of the early 21st century, models are mostly bought by collectors and re-enactors. Its design has influenced the production of numerous other models from other companies.
The Colt SAA revolver is known as "The Gun That Won the West".