I tend to keep my stuff in zip locks bags inside the can, be it plastic or metal (not sure that would have made a difference, between the seal fail and the weight of the water probably deforming the plastic and defeating the barrier). Cool test though. I hope you were able to salvage some on that aquatic ammo. Price diff on metal vs plastic is negligible so it looks like Metal it is for me. Were you able to clean up the metal cans and make them serviceable again (non aquatic)? Maybe a water proof paint can be applied? Anyone any ideas?