I have looked through my books for Ashbury and come up with a Joseph Asbury listed as a barrel maker at 11, Weaman Street, Birmingham. Apparently his barrel machinery was purchased by A.A.Browns.

This is the little 2" Tolley with the JA stamp: This petite 12 bore weighs in at 5 pound 2 1/2 ounces. Needs a bit of a clean up. Lagopus.....