Some of my old SxS's have brown oxidation in their engraving cuts. The receivers are fairly bright, but the rust is below the surface so it doesn't get worn off when carrying and shooting the gun. Does any one have a good method of cleaning the engraving cuts without scratching or damaging the receiver? I've tried wiping with with Hoppes bore cleaner and some of the rust does come off, but the rest of it looks darker than before. Has anyone tried a mild soltion of muriatic acid (hydrochloric acid) which would then be neutralized with a baking soda solution? I read that will remove black iron oxide (bluing). Why wouldn't it remove brown iron oxide? Any other ways to do this? Thank you for ideas.
