The Model 1873 Trapdoor Springfield was the first ever standard issued breech-loading rifle for the United States Army. It was produced in two versions: an infantry rifle with a 32 5/8 inch barrel, and a cavalry carbine with a 22 inch barrel.

The cartridge was designated as ".45-70-405", indicating a .45 caliber, 405 grain bullet was propelled by 70 grains of black powder. It had a muzzle velocity of 1350 feet per second in the rifle, a powerful and effective load for the military skirmish tactics of the era. A reduced-power load of 55 grains of powder (.45-55-405) was manufactured for the carbine, to lighten recoil in cavalry usage. It had a correspondingly reduced muzzle velocity of 1100 feet per second, and reduced effective range.

The rifle was originally issued with a copper cartridge and taken off to fight the American Indians in the American West during the second half of the 1800s, but the soldiers soon discovered that the copper expanded in the breech when heated upon firing and sometimes jammed the rifle, by preventing extraction of the fired cartridge case. A jam required manual extraction with a knife blade, and could render the rifle useless in combat except as a club.

After the annihilation of General George Armstrong Custer's battalion (armed with the carbine and .45-55 ammunition) at the Battle of Little Big Horn in 1876, jamming of their rifles was asserted to have been a factor. The rifle cartridges were redesigned with brass instead of copper cases, which did not expand as much. This proved to be a major improvement.

Although the tested accuracy of the .45-70 was approximately 4 inches at 100 yards, the heavy, slow-moving bullet had a "rainbow" trajectory, the bullet dropping several feet at ranges greater than 500 yards. A skilled shooter, firing at known range, could consistently hit targets that were 6 X 6 feet at 600 yards - the Army standard target, and a skill mainly of value in mass or volley fire, since accurate aimed fire on a man-sized target was effective only to about 300 yards. A 500 grain load was developed in 1879 which was lethal to a range of 3500 yards, although the possibility of an aimed hit at this range is near-nil.

The men of the Army, after Little Big Horn, were required to take target practice twice a week on target ranges and became so proficient that many of them won awards that were offered by the armed forces for their riflemanship.

If a soldier could hit a target eight times out of ten at 600 yards they would receive the Marksmanship Award, but if a soldier could hit the same target eight time out of ten at 1000 yards they would receive the Sharpshooter Award. Many of the men were marksman, but very few of the men were sharpshooters and a great deal of respect was given to those that could achieve that task.

Rifles of the United States