I recieved a nice hunting double 12 gauge today and upon looking at it, ther seems to be a coat of varnish over what I believe is the original finish. Now I don't want to try and restore this gun to like new condition, but I would like to try and remove the varnish and clean up the original finish. Any suggestions on how to remove it without damaging the old stuff? In some areas I can chip it off with my finger nails so it's not really bonded to it. Is there a solvent perhaps that can help?