I don't think freezing powder would be a problem IF you : 1. Put the cans in zip lock bags, sealed, and 2. put some kind of desiccant ( available from hobby stores, hardware stores, Home improvement stores, etc.) in the bags with the cans. The Desiccant will remove any moisture in the bag, and also help suck out moisture that might be in the can of powder. The desiccant protects the cans from rusting during storage.
I would do this whether I was storing the powder in a freezer, or in a working refrigerator. Actually, the insulation for either a freezer or refrigerator is enough that the powder is going to stay cool and dry inside.
I suppose if the freezer was sitting on a concrete slab, out in a hot sun, that the temperature inside could rise too the 160 degree range, but this is way below the ignition temperature of Black Powder. And just because the inside of the refrigerator might get that warm, it doesn't necessarily mean that the powder in its container will also get that warm.
I would not store Opened cans or bottles of BLACK Powder in a working freezer or refrigerator. Once you open the can, you let air and moisture inside, and that moisture would be subject to freezing ON THE INSIDE OF THE CAN. When the can is removed, its likely to " melt, and contaminate the powder. Likewise, as someone else has already noted, I would not open up a can of powder that has been frozen until it has had time to warm up to ambient temperatures. Just removing the can from the freezer should produce frost on the outside of the can when placed in 70+ degree air temperatures. ( Think of frost that forms on the outside of a container of ice cream.)
I don't think freezing powder is necessary. Leave the space in your freezer for venison, and other game!
I double bag any powder I store- with the zip lock bags being put inside another bag- like a garbage bag-- which is tied shut before the package is placed in the refrigerator( or freezer).
A friend had the motor on his freezer stop working one Saturday night, and he had a mess to clean up the next morning, as everything he had in the freezer was melting, and water was streaming out the bottom of the freezer to his floor drain. He told me that he is not going to put stuff in his freezer again that is not double bagged, just to keep the moisture from ruining printed tags on other bags. He had a difficult time figuring out what he had after he moved the stuff to another freezer to save it all.
If I had a freezer, or old refrigerator, sitting in my garage, where its shaded, and the concrete slab under it helps to keep the garage cool, I would not bother turning them on if all I was storing there is powder. The cans would be bagged, as I have described above. :thumbsup:
