One of the 7,000 U.S Model 1840 Flintlock Muskets manufactured by Lemuel Pomeroy of Pittsfield, Massachusetts, between 1840 and 1846. It was subsequently rifled, fitted with a long range rear sight, and converted to percussion using the Belgian "cone style" method. It has the standard markings including "1844" on the lock and "1842" on the barrel. The barrels were originally made extra thick in anticipation of them being rifled later. The Model 1840 muskets were the last U.S. muskets with flintlocks and many were actually converted to the percussion system and rifled before they were even issued to the troops. They were primarily used during the Mexican-American War, but some were also used during the Civil War. A "US" marked socket bayonet is included.

The Model 1816 muskets had very long service lives. This example was manufactured in 1832 and then converted to percussion for use during the Civil War. It is dated "1832" on the lock and "1861" on the breech plug/tang. "H&P" is marked on the breech seam, and "NJ" (New Jersey) is on the left. "Backwards" style three-notch rear sight and blade front sight on the front barrel band.