Seriously, folks. I grew up around a bunch of preppers and general outside-the-law folks. Burying things in ammo cans was kind of a pastime of a lot of people I knew.
It's _really_ hard to find something like that a year or two later, even if you think you know exactly where it is.
I've been the person wielding the shovel to dig up a box of important stuff before. (Thankfully, not mine, I was just the teenage labor.) We dug a lot and never found it. Also, tree roots grow over/through things and people _love_ to bury things at the base of a tree. Kinda hard to dig through roots.
Don't bury things you want to find later.