If I was to bury a gun and ammo in the back 40, how deep would you go. Too deep and it is too hard to dig up in a hurry when needed, too shallow the freeze thaw cycle maybe a problem. The stuff is in PVC tube with threaded end caps. I dont need to worry much about metal detectors the back 40 has more scrap metal and trash piles than you can count. The former owner was to lazy to drive the three miles to the county dump.