There will be a few of you folks are into this, most maybe not. Some years ago I put three tubes into the ground with AR mags and ammo in them. Well with all the hard times finding ammo and the prices going up I thought I'd check my tubes and inventory the contents. So of the 3 I put in the dirt, I found 1 of them, These are my observations on what i'd do differently next time. 1) Find some way to mark the location, an example would be lining the hole up with a tree or something, line of sight. 2) use a set depth when possible and measure that depth. 3) lay some brightly colored flagging tape across the tube, maybe in a cross pattern wider than the top of the tube and possibly a couple inches higher. 4) Mark the tube itself as to where it should be cut open at to minimize damage to contents. I'll say that it was 4" pvc with caps glued on and then siliconed on the outside. The contents were in excellent condition and showed no signs of leakage. The ammo I pulled out was Winchester Q3131 with headstamps of 07/08. so I guess about 3 to 4 years in the ground. I'm 6 mags richer now too. Post up with your thoughts I figure most will want to keep it to themselves.