On the history of the weapon:

George Washington decreed that a second state-owned weapons factory should be built next to the Springfield Armory. The picturesque town of Harpers Ferry on the border between Maryland and Virginia was chosen because of its strategic location and the possibility of using the water power at the confluence of the Potomac and Shenandoah Rivers. The property was purchased in 1796, construction of the weapons factory began in 1799, and in 1802 25 employees began producing muskets and pistols. During the Civil War, at which time around 400 employees were employed here, the weapons factory was destroyed and never rebuilt.
The `Model 1805 Flintlock Pistol´, 4,096 of which were manufactured in Harpers Ferry from 1806 to 1808, was the first service pistol of the US Army to be manufactured in a National Armory, after the Army had already purchased 2,000 `Model 1799 Flintlock Pistols` in .69 caliber from the company S.North & E.Cheney Berlin, Connecticut. In contrast to its predecessor with a box lock and free-standing barrel, the Model 1805 Flintlock Pistol was stocked and had a sidelock. The barrel was smoothbore and had a length of 10 1/16 inches.