Each rifle has its own Pelican 1720 Case. I probably should get some dessicant packs to throw in. There were just a couple of tiny pits forming on one of the bolt carriers. I think those cases are good to go, and I may have panicked a little. My only concern with storing the BCG's in motor oil would be deterioration of the "O" ring... but that worry is probably unfounded. The area is normally very low humidity, but does experience extreme temperature changes at various times of the year. That said, I do not know what the ambient humidity was when I closed the rifles up a few months back. I sort of planned ahead a little when I built the rifles; knowing they would be stored a lot I used stainless barrels on all of them. Yup, that was the main reason (95%) I chose stainless. It really had little to do with accuracy or any other reason. I will check out Cosmoline and those special bags. Thanks for the tips guys!