Is this an original Enfield P53 converted to a shotgun? [Not a Lee-Enfield, that is a much later bolt-action magazine-fed rifle.] Or is it a modern replication? If it is an original Enfield, then no form of documentation is required to own it, but if it is used to shoot blanks, as in re-enacting, a Shotgun Certificate is required to possess it and or use it. The same shotgun certificate is needed if it is a modern reproduction firearm. Did you check that aspect out?
This firearm would suit the needs of an American Civil War re-enactor or British empire Victorian Army of the time before the adoption of the Martini breechloader.
This shotgun is a muzzleloader - that is to say, the powder, wads, shot-load and more wads are loaded down the barrel from the open end. A percussion cap is then put on the nipple, and then the thing can be fired.
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