Greener records indicate the gun was made about 1892. I would definitely take that "finish" off and have the gun reblued which would add to the enjoyment of it. There are several good guys to do a rust blue for you.
However in looking at your picture again, I see indications of a laminated or Damascus barrel , so check it after that mess is taken off to determine the best new finish to use.

Last edited by Stallones; 05/18/15 01:48 PM.