Burnside received a U.S. patent for his design of a breech-loading carbine rifle. This invention was a key factor in the establishment of the Burnside Rifle Company.

Burnside continued to improve his carbine design and obtained additional patents for modifications and enhancements. These improvements aimed to increase the rifle's reliability, accuracy, and ease of use.

The Burnside carbine was widely used by Union cavalry troops during the Civil War. Its breech-loading design allowed for faster reloading compared to traditional muzzle-loading rifles, giving Union soldiers a tactical advantage. It proved very useful throughout the conflict.