I can't help but be very skeptical of family attributions. I have an acquaintance with a long family history in the colonies, Society of the Cincinnati, etc. all very, very well documented. A direct relative was on Bunker/Breed's Hill that day, again wonderfully documented and the family has a Bess claimed to have been used by said relative on the battlefield. While some of the parts are Rev War including the lock, peculiarities of the stock, barrel, other parts clearly indicate a 1790s period - likely a re-stocked and cobbled-together militia musket using many war-time Bess parts. I'll never tell.