The so-called M1795 muskets (Charleville Pattern Muskets in period documents) were in production at both Harpers Ferry and Springfield as late as 1817.
References:
American Military Shoulder Arms: From the 1790s to the End of the Flintlock Period - George D. Moller
and
U.S. Military Flintlock Muskets, and Their Bayonets, the Early Years, 1790-1815 - Peter A. Schmidt