EJSXS, On looking closely, I would bet money your A&N was made by Lancaster! University of Glasgow at enquire@archives.gla.ac.uk may be able to give you some history on yours, though the archives are incomplete. I found them most helpful- give them the serial #, and a description, and they will do 1/2 hr research at no charge. At any rate, the engraving style, rifling description, even bore and groove diameters are virtually identical to my Lancaster.
Doug