The Springfield Model 1873 was the first standard-issue breech-loading rifle adopted by the United States Army. The rifle, in both full-length and carbine versions, was widely used in subsequent battles against Native Americans.

The Springfield Model 1866 was the second iteration of the Allin-designed trapdoor breech-loading mechanism. Originally developed as a means of converting rifle muskets to breechloaders, the Allin modification ultimately became the basis for the definitive Springfield Model 1873, the first breech-loading rifle adopted by the United States War Department for manufacture and widespread issue to U.S. troops.