Dan: That is why I wrote my post as carefully as I did. I said SMALL rag- not large. I said take your time, and let the chemistry do the job- and NOT try to scrub off the tarnish. I ended by saying to rinse off the stock, and use paper towels to soak up the moisture( acid ) that might get down into the cracks.
All the products that are sold to remove tarnish involve reagents- combination of acids and salts. Some add abrasives. I don't like Abrasives, and particularly don't like them used on an antique!
Journeyman did not make it clear whether his gun is an antique( original) or just an old modern made gun. Several members here have posted comments about this confusion.
I have cleaned brass on older guns using a mild acid, and then dipping my rag into a teaspoon of salt with my fingertip backing the rag. It allows me to go into fairly small places without slopping over onto the wood. Sometimes, with the fancy patch box designs, I have had to resort to using Q-tips to apply the acid/salt compound to do the job CAREFULLY.
I certainly encourage people to use painter's tape( Blue colored masking tape) to protect finishes, and "crack" around inlays, if its obvious that the crack is large, or has no finish in it sealing the edge of an inlay. I have used paste wax to fill such cracks temporarily so that no fluid can get down into the cracks as I am cleaning the metal( brass, silver, steel, aluminum, etc.
If you use Bore Butter or "Wonderlube" or any patch lube that uses wax in it, there is no need to buy a furniture polish, or car polish that has wax in it. Use what you have to seal those cracks before working on the metal tarnish you want to remove. :thumbsup: