I really like Birchwood Casey Sheath and I also use RemOil. If you bring guns in from the cold, take them out of the case and let them lean against a wall overnight so that all of the condensed moisture can dry off before you wipe the metal down. Do not store them in cases- its best to store guns where they are exposed to ambient air conditions. I keep mine in a wooden cabinet and a few in my basement workshop- both areas can get somewhat damp at times, but I've never had any rust- well except on a POS Rem 597.