Okay, I need your help. New to this muzzle loading sport and have had this wall hangar that has been passed down thru the family for years. I've had it for +30 years. The story that came with it is. "It was a Hudson Bay Trading rifle that was used to exchange pelts for the rifle, hence the long barrel." Because of the patina of the rifle I assumed it was brass, but now that I've been bitten by the BP bug it piqued by interest in this " wall hangar". I put a magnet on it and its not brass. The bore is .550 at the muzzle, smooth bore. Muzzle thickness is .130 and has a definite crown or recess ( shown in photo). The lock is broken, by my son I think, many years ago. Overall length is 67.5". There is an Eagle clutching arrows(?) on the lock plate. Barrel bands have numbering on them. Brass serpent on opposite site of lock.