Am piecing together a FW field grade 12ga. The frame has been sitting a very long time and is entirely a solid brown. I'll not be color casing, but I would like to card off the brown and end up with a coin type, or French gray, type finish. Triggers and guard will be rust blued with the new barrels.
What is the preferred method to remove the old brown patina? Haven't dealt much with this degree of brown before.