The first standard issue breech loading rifle issued by The US Military, The Model 1873 popular among Frontier US Army Units (still involved in The Indian Wars). A carbine version was also manufactured. Roughly 50-inches long, it also featured a bayonet attachment and a flip range tangent. Designed to use a .45 Caliber brass cartridge, it was capable of firing up to 10 rounds per minute. It had a maximum effective range of 1,100 feet. Although still in use by the time of The Spanish-American War, the primary drawback with the Model 1873 was that the soft cartridges would jam (so much that a knife had to be employed to pry out the round). This was never so evident as it was at The Battle of The Little Bug Horn River, when The 7th Cavalry (using the Model 1873) – were massacred. The name “Trapdoor” comes from the Drop Box-type of cartridge opening (which folded outwards). It was located at the top of the weapon.