I recently opened a sealed battle pack of German MEN surplus and I was surprised to see a lot of corroded rounds. After some diligent cleaning, most of it was salvageable with only a handful having the dreaded pink corrosion. I noticed almost all of the corroded rounds had been in direct contact with the sides of the cardboard box. After researching it seems they had a reaction with the chemical residue in the cardboard. This got me thinking about my other stored ammo.

I keep all my ammo, even the long term stockpile, in their original cardboard boxes. This makes it easier to trade, count and to tell what lot my ammo is if there happens to be a recall. Is this a bad idea? Should I be pulling them all out of the boxes and just storing them loose in ammo cans?