I have stored many over the years....the biggest loss of shotgun hulls I have suffered was due to mouse piss. Make sure you close them up in something that mice cannot enter and they will be fine. I don't understand the need of a mouse to get on shotgun shells and piss, but don't think you are immune because you don't see mice around. Maybe they subscribe to the same philosophy as all dogs..."if you cant eat it or F it, then piss on it"
I think the smell of gunpowder must be like something they can eat and when they get there and discover it's not........."piss on it"
