The Colt M1877 was a double-action revolver manufactured by Colt's Patent Fire Arms from January 1877 to 1909 for a total of 166,849 revolvers. The Model 1877 was offered in three calibers, which lent them three unofficial names: the "Lightning", the "Thunderer", and the "Rainmaker". The principal difference between the models was the cartridge in which they were chambered: the "Lightning" being chambered in .38 Long Colt; the "Thunderer" in .41 Colt. Both models had a six-round ammunition capacity. An earlier model in .32 Colt known as the "Rainmaker" was offered in 1877.