Hi, I recently purchased some old hammered shotguns and try to define their age and Gunmakers if possible. I am threading here for one of my shotguns, the Birmingham made one. It is 30" shotgun, with no makers name on it. The proof marks are a crowned BP (calligraphy) on barrels and on the action the following marks appear: BP BV and NP (all crowned), 12c in a diamond, Nitro Proof 1 1/8, 13/1, CHOKE on the left barrel only. (Marked yellow on attached proof mark table)
Also, the number 411 appears on action, forend and barrels, so it must be the Serial Number. A crowned BV also marked on