That blob may be a reinforcement for the joint of an extention to the caplock, to reach the forward lock bolt of the original inlet. That seems a long inlet, but that is probably what the original flintlock was. We need a photo of the sideplate, with the measurement of the centers of the lock bolts. If there are keys still holding the stock on, and the breech has not been cut back and pins now used to go through the underlugs, with the keys still stuck through the stock, then almost certainly the muzzle end has been cut off. I can't see a nose cap. You will want to get measurements from the breech to each stock key and the muzzle, and from the front of the entry pipe to the center of the rod pipes and muzzle. Those clues finally helped me realize the Jacob Wigle rifle I restored had the breech cut off and was re-breeched for caplock and that the muzzle end had been cut off. Present barrel length is 35.5, but the original was 46 inches, like others from Westmoreland County. (Folks, this is part of our discussion on another website, and the rifle I am discussing is one made by Jacob Wigle, and which I discussed on this forum. My post is somewhere in the archives, I have not tried to find it). The solid clue that the Wigle barrel had been so long was the balance point of the rifle. So look for wear marks of carrying, that would be the balance point. Pack rats had chewed on the Wigle stock for salt, so it was really obvious.