This is a William Powell, patent #1163 0f 1864, Bar In Wood shotgun,it is not a conversion from muzzle loader. I have a framed copy of a William Powell poster, showing this exact gun. A copy of this poster can be seen on page 93 of Douglas Tates book ,"The Birmingham Gunmakers."
Powell,s gun sales registers are excellent, I am sure they would be pleased to confirm the above.


Roy Hebbes