Pulled an RCBS mold from my stash today in order to cast up some boolits for a trial tomorrow. I noticed a light rust in patches along the top of the mold and in the cavities. I then ran the mold across my brass brush on my grinder, heated, cast, and could find no real problems.
Now, the mold was kept in the original box with the "oil" paper in it. The last it was used was about 2 months ago and was completely cooled before returning to the box.
Question is, what do you fellas use to protect steel molds for long-term storage? I have WD-40 and Ballistol {all natural...great stuff for case lube}. Any other suggestions?