Spencer Model 1865 carbines with six-groove rifling were serial numbered in the approximate range 1-23000 and manufactured circa 1865-1866. The top of the barrel is marked "M 1865" at the breech. The top of the receiver has the Spencer Repeating Rifle Co. three-line address/patent date marking. The left of the stock has two boxed script inspection cartouches. It has a ladder rear sight graduated to 900 yards, and saddle ring mounted on the left of the stock. Many of these late Spencer carbines were used into the late 19th century Indian Wars.