Bill when i store mine for an extended time.I have these gun socks that are silicon impregnated that you slide over the gun and it protects it from moisture ect.They are relatively cheap and i have never had any rust or corrosion on my guns since.
But if you don't like that idea i would use just plain ole gun oil.And if they are kept in a gun safe make sure you have a good silica bag in there with them to soak up any unwanted moisture.:D