"Here == a little science experiment: Get a large jar. Dry it completely inside. Toss in a paper towel. Screw the lid on tightly, air tight. Now, put it in your fridge for a few days. After a few days, you'll see condensation inside the jar. The paper towel will be damp."
Sort of like the science experiment where you put a box with rags and a handfull of cat food in a barn, and when you open it there are mice inside?
In your "experiment" above, one of two things is true:
(1): Nothing is there that was not there before, it's simply redistributed.
or
(2) The jar leaked and allowed something else to enter.
You cannot seal a container and "grow water" from air. But your point is made, which is that the air inside the jar contains water when sealed in the form of water vapor, and that water can be condensed out to liquid water with a temperature change. Naturally if you had done the same experiment in the Mojave Desert, where the humdity of the atmospheric air that you seal into the jar is near zero, you would be hard pressed to duplicate it.
Lesson #1: If you are going to seal something in a jar, seal it with as dry a gas as possible, and toss in a dessicant bag to keep that water someplace away from the other goodies in the jar.
Observation from fact: I have a friend who owns an aircraft salvage yard. Out in the yard is a pile of what look like soup cans. All of them are from the 1940's. Contained within each one is ONE small Lockheed aircraft part for a P-38. One small spherical rod end bearing, one small rubber seal, one small "anything". The labels are all long gone and when we are bored we will grab one, open it up, and wonder at the quality of the object and the fact that it looks brand new. Good packaging is the key.
Now then:
IF you wanted to bury objects, and I am not saying that you should:
1: Prepare the objects themselves, IE: coat the metal with a thin layer of spray-on preservative oil, such as LPS-3. You want a waxy coating that will not move under the pull of gravity once dried.
2: Place the objects into bags that are then vacuum-sealed. All you need for a rifle or shotgun length object is a seal-a-meal vacuum bagger from Walmart and a roll of the self-cut tubing that you use to make your own bags. Seal one end, slide the object into the other end, add a dessicant bag to absorb the small amount of water vapor that will remain in the (little) air that will remain, vacuum tight, and seal the other end.
This is exactly how I pack many steel objects that I store on my boat (tools, spare parts, etc), and mimics military long-term storage procedures. The military would use foil lined vacuum bags, but the other processes are identical. In VERY missiion critical stuff the inside of the bag is inerted with dry nitrogen. No oxygen = no oxidation. That's probably a bit of overkill here.
At this point the object inside will look the same in 1000 years *if the bag remains intact*.
So: Keep the bag intact.
(1): Protect it from Ultraviolet Light.
(2): Protect it mechanically.
For direct burial:
Place the vacuum-bagged goods into a second rigid barrier tube:
PVC Pipe lengths capped on each end, are ideal. You can either simply glue caps on both ends, or glue a cap on one end and a cleanout fitting on the other end. Diameters can be varied according to what you need to preserve. Never put all of your eggs in one basket: If a tube is damaged you do not want to lose everything. Distribute your objects into correct sized containers and deal with each one individually. Once again, this is a way that have stored things on my boat for years, and it works in direct contact with water.
Rifles and Shotguns should be disassembled for size reasons as well as keeping wooden stocks away from metal. A bolt action rifle action and barrel can fit into a pretty small diameter tube. Stocks are fit and try into larger diameter PVC. Once objects are into the tubes you can "pour and shake" ammunition into all of the spaces around them to completely fill the tubes. Less air = less condensation from the trapped air so use ammunition (or marbles, or whatever) to fill up the voids. Always place large dessicant packs into both ends of the tubes. Remember that these are to dessicate the trapped air, not to deal with any leakage. Leakage must be zero. Glued on PVC end-caps are the gold standard for that.
To summarize:
Place a preserved object into the smallest volume of dry air, seal it in, and protect it mechanically.
Oiled and vacuum-bagged objects placed into dessicant-pack protected glued PVC tubes are going to survive for longer than any of us will be alive.
I have to say that my vacuum-bagger is one of the most useful tools I own. Living on a boat, I bag everything: spark plugs, tools, rice, sugar, ammunition, even my winter clothes when we switch to summer climates. Even back home I use them to segrergate and contain all sorts of things in the shop and in the kitchen. Buy one and see.
Guns for the OP? Personally, I would sell them and buy new ones when I came back.
Willie
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