The Model 1842 was the first firearms manufactured at both Springfield and Harpers Ferry with totally interchangeable components. It was also the last of the U.S. martial smoothbore muskets and was specifically manufactured with a thicker barrel in anticipation of the fact that many would later be rifled. This very fine Model 1842 is dated "1846" behind "SPRING/FIELD" vertically at the rear of the lock and on the barrel tang. It has the standard "eagle/US" on the center of the lock and government proof and view marks on the upper left at the breech. The left flat has a "JAS" cartouche. It comes with a socket bayonet with a leather scabbard and hanger.