The Colt Single Action Army is (unsurprisingly) a single-action revolver that can fire six rounds of various calibres, such as .45 Colt, .44-40 Winchester, or .357 Magnum. It was designed by Colt’s Patent Firearms Manufacturing Company for the U.S. government service revolver trials of 1872 and was adopted as the standard-issue pistol of the U.S. Army from 1873 until 1892. The handgun has a metallic cartridge system, a flat leaf spring mechanism, and a half-cocked position for loading and unloading. It comes in different barrel lengths, from 4 + 3⁄4 inches to 7 + 1⁄2 inches, and has a blued or nickel-plated finish. The Colt Single Action Army is also known as the Peacemaker or the M1873 and is a iconic symbol of the American Wild West era, used by ranchers, lawmen, and outlaws alike.