Patented 1864 this carbine is known as the Remington Type 1 "Split Breech" or Remington-Rider Civil War Carbine. Caliber 50 Rimfire (56-50 Spencer). Standard carbine 20" round barrel and saddle ring.
This little carbine holds a number of distinctions in the history of American firearms. It is considered to be the first metallic cartridge long arm to be produced by the Remington Arms Company, even though they outsourced the production to Savage Revolving Arms Company of Middletown, Connecticut.
It was also the last pattern of military carbine to be delivered to the US government during the American Civil War.
The “Split Breech” was also the direct predecessor of what would become the most widely used single-shot, breech loading, military rifle action of the 19th century; the rolling block.
The development of the split breech action is attributed to Remington’s Joseph Rider, who was responsible for the myriad of Remington-Rider firearms designs.