In 1873 the caliber of the “Trapdoor” rifle was again reduced, this time to .45. Since it was not practical to convert .58 caliber muskets to this small size, Springfield Armory began new construction of the “Trapdoor” rifles. They remained in production, with modifications, until 1893. This was the weapon, both rifle and carbine, that served the U.S. Army so well during the Indian Wars on the Western Frontier and in the Spanish-American War. In twenty years of production almost half of a million .45-70 caliber weapons were manufactured at Springfield.