45-70 – or 55 grains of powder for the lighter cavalry carbine. 45 cartridge was loaded with a 405-grain bullet and 70 grains of black powder for infantry rifles – the reason it became known as the. 45-caliber round, screwed into a trapdoor “action.” The. Instead it featured a separate barrel chambered for a new. The Model 1870 was replaced in 1873 by a new trapdoor Springfield, which was not a converted muzzleloader. 50-70 conversion went through several variations from 1866 to 1870, when both an infantry rifle and cavalry carbine were produced. Product prices and availability subject to change without notice. Get the latest information about new products, special deals, news, top-rated items, promotions and more. 50-70 conversion was a success, and its first major action was the famous Wagon Box Fight of 1867 in present-day Wyoming, where a handful of soldiers from nearby Fort Phil Kearny, along with a few civilians, held off several hundred Indian warriors led by Lakota (Sioux) Chief Red Cloud, thanks in part to the rapid repeat fire from the cartridge rifles. SP0178 Hammer Screw (Original) For 1873-1889 Springfield 45/70 Trapdoor (0 reviews) Login to Write A Review. (The original barrel length of the muzzleloaders was 40 inches, but the breechblock reduced that to 36.6 inches.) 50-70 cartridge using a 450-grain bullet and 70 grains of Fg black, resulting in 1,260 fps from the 36.6-inch barrel. 50 caliber and chambered for the new centerfire. 58’s ballistics were comparatively wimpy due to the pressure limitations of the copper rimfire case, while the smaller parts of the breechblock were complicated and failed too often.Ĭonsequently, in 1866 the second Allin conversion appeared with a less complicated breechblock, including a U-shaped spring extractor that flung fired cases out of the chamber, whereupon they hit a wedge-shaped steel block in the “trough” behind the chamber, launching them into the air. 45-70 caliber answered to all the exigencies. These rifles were called the Model of 1865, but unfortunately the. Between 18 appeared the first transformation of a muzzle loading Springfield musket made by Allin and in 1868 the first Trapdoor Rifle was built, further modified in 1870 three years later a new rifle in the. 58 rimfire cartridge loaded with a 480-grain bullet and 60 grains of black powder. The first trapdoor Springfields were 5,000 muzzleloaders chambered for a. Alexander Dyer, Chief of Ordnance, but Allin assured the general the Army could use his design without paying royalties. Allin personally patented his system in 1865, unbeknownst to Gen. His design removed a few inches off the top of the rear end of the barrel the gap was then fitted with a steel breechblock hinged at the front (hence the nickname “trapdoor”) containing an angled firing pin. Allin, master armorer at Springfield Armory. Several people came up with workable conversions, but the winner was developed by Erskine S.