Re: Simeon North 1822 percussion with Octagon Barrel?
To add a bit, FWIW. The lockplate, though converted, is original, as are the trigger guard, trigger, and rear of the stock. The inspector's mark is correct for the original gun; LS was Luther Sage, a Springfield Armory sub-inspector. The rifled barrel and the bolster are not original, nor is the hammer, and the foreend of the stock has been cut down. The conversion was not done by an armory or under military contract; it is a gunsmith job.
The slot behind the hammer was for a sliding safety, now gone; the Model 1819 was, AFAIK, the only U.S. flint or percussion military pistol to have a safety.
Just another case of someone making an up-to-date gun out of a piece of military surplus junk.