Howdy pard,
I've used tennis balls and coke bottles. I think I like using the gun, the best. I don't have any rust worries.
Right now, I'm thinking about putting a ziploc bag around my pistola and then sticking that back in the holster. Or, I'm gonna have to make a whole new drawer area to keep my leather... I'm still searching for a way I'm liking to store my leather.
(the tennis balls are cheap and easy)
Adios,