These Colt muskets were produced throughout the Civil War under contract with the Union and state governments. An estimated 100,000 muskets were manufactured by the end of the war. This model is based on the Enfield Pattern 1853 and has many features incorporated in the Springfield Model 1863. This 1864 dated example has the standard markings and features, including an "M.N.M." inspection mark on the left at the breech and "AWM" and "JT" cartouches on the left stock flat.