The key identifying marking on this musket is the "IP" on the left stock flat. This is the mark of Joseph Perkins, the superintendent of the Continental Armory in Philadelphia in 1780s. The armory repaired and refurbished muskets and also built muskets from a variety of parts for the Continental Army. It evolved from the earlier Continental Gun Factory in Lancaster. These muskets are incredibly rare. The left stock flat and the lock are marked "US" which is noted on the Continental Armory muskets. The bottom of the stock in front of and behind the trigger guard has a "+" marking. The furniture is brass. The "S" side plate is based on the French muskets of the era, and the trigger guard and buttplate are the same style seen on other Continental Armory muskets. The latter has a more simplified tang than the Brown Bess muskets which would have been both easier to produce and mount and also used less material. The barrel has no visible markings. The stock has some cracks and splinters typical of these muskets given the stocks were made before there was time to properly season the wood due to the urgent need for arms. It has an iron ramrod.

Good as professionally reconverted to flintlock configuration. The barrel and lock have dark brown patina, moderate pitting, and moderate to heavy overall wear. The cock, frizzen, and pan are artificially aged to match. The brass also has very dark aged patina. The stock has several cracks, some slivers absent, chip on the left side of the butt, some insect holes, and mild overall wear. Mechanically fine. This is an incredibly rare musket. Genuine muskets with Joseph Perkins' mark are very scarce with only a small number known and even fewer in circulation.