yes, once buried a rifle, ammo, food, clothes, first aid, etc on some rural property.

first i taped it all up inside heavy duty garbage bags then in a 3x3x3' military "water-proof" aluminum box.

came back a few years later to find it had leaked. serious damage was done.

so if doing this, be absolutely sure its really water-tight.

the other thing i learned was that dirt compacts tightly above and around the container over time. it took much much longer to dig out than i had planned, and needed more than bare hands to do it, so should have hidden digging tools nearby (and above ground too).