Provided you have a safe place to lock them up, and you can find them in top-notch condition, these can be very handy cases for sealed storage.
I like that, I have been thinking of repurposing some of my ammo cans. I have a fairly good safe set-up but need some expansion room. I have multiple layers of locked storage so I am not hugely concerned. Plus, camouflage is always the first line of defense strategy.
Thanks for the other info too, going to have to try that.