I live on a salt water canal in Hawaii. You cannot possibly get a more corrosive environment than that. Even a well oiled gun left outside for a week will begin to become corroded. However, the guns in my safes each with a generic golden rod are dry and corrosion free after years of storage. I do take them out about twice a year and wipe down with an oiled cloth.

Great-Great Grandson of D.M. Lefever
www.lefevercollectors.com