Many preppers (those that are going for the long term) use moisture absorbers in their food, ammo, and other storage containers and caches.
I recently re-discovered an old technique for DIY desiccant packs that is much less expensive than purchasing them complete and outright, even when one makes bulk buys.
As background, the actual desiccant medium used for moisture absorption is Silica Gel. Now one can look at places, like Amazon, and confirm that this stuff sells for upwards of $15 per Kg (2.2 pounds). Even then one is faced with the task of packaging it in suitable sizes to fit in their containers. So many people just buy the prepackaged size they need at the time, resulting in a lot of wasted funds over a good DIY method.
A great redeeming feature of Silica Gel is that it can be “re-activated” simply by placing it in a 250 degree oven for an hour or two, thus it can be reused indefinitely. (I always save and reuse/repackage the desiccant packs that are sometimes packaged in electronics and other things I buy, as I am sure others do also.)
Bulk Silica Gel can be reasonably purchased LOCALLY if one knows where to look. It is widely used by florists to dry and preserve (mummify) freshly cut flowers. Your local florist may sell you some on the cheap, especially if you intimate that you are a dried flower fanatic who wants to preserve some especially nice home-grown ones, or if you are experimenting with making home-made potpourri.
However, the quickest way is to just buy it from Hobby Lobby, or sometimes Walmart. At Hobby Lobby it is sold under the trade name “Dri Splendor” in 5-pound bags for $14.95. Look for a a blue/lavender sealed plastic bag with bright yellow flowers near the top. It says “Silica Gel” right on the bag. I find that many store employees don’t even know they have it, so just wander around their collection of dried flowers until you spot it. It’s there; believe me. This silica gel has “indicator” beads dispersed in the white gel beads. When it is new, the beads are blue. When they turn pink, they are much less active and it’s time to renew them by simply placing them in an oven for awhile.
Most Walmarts have it, also. Just visit their crafts section and look around.
Here’s how to repackage it for individual use.
I use two methods. The simplest is to use small 2X2 oxygen-stripped paper packs, like are commonly sold for DIY tea/herb bags. The ones I use are heat seal-able using a standard iron on the cotton setting. Here is an example. There are many more examples, and if you are lucky, you can find them and many other sizes at your local health food store, or an ethnic food store.
There is a second method. Sometimes one needs a larger or different shape/size bag, especially for ammo storage in ammo cans, or say 22LR in small lots. For this, I use old, freshly laundered cotton sheets, T shirts, or other cotton fabric; I cut it into pieces that can be used to form or fold into the properly shaped bag. The odd-shaped cotton trimmings can be re-purposed into cleaning patches for your guns.
Again, at Walmart, Hobby Lobby, and some other stores, you can buy this wonderful material that is heat sensitive cloth adhesive. It’s typically used to seamlessly repair rips and tears in clothing. You can also buy the equivalent as liquid in a squeezable tube. The heat-sensitive tape can be trimmed with scissors into very narrow strips and used to seal the cloth bags you have made, and the liquid simply spread along the seams. Either is sealed with a hot iron.
In any case, one side of your bag is left open until filled with Silica Gel, and then is permanently heat sealed.
Some ways I use them–
For barter storage, I find that the very small 3-ounce mason type jelly jars are ideal for holding 50 rounds of 22LR and a desiccant bag, and if the metal ring is coated with two coats of clear krylon and placed in a ziploc freezer bag, it is suitable for even direct burial. The half pint jars store 20 rounds of .223, 7.62 or .308 reasonably well also. The pints are great for shotgun shells.
The larger size mason jars can be used for all sorts of dried food storage, such as beans, as well as repacking large cans of mountain house stuff into smaller portions, A vacuum-style food sealer system is used to evacuate air from the newly made packages of mountain house, which I arrange to purposely be a “serving”. I vacuum seal the stuff in plastic bags separately because of cross taste/scent contamination, and then I put a home brew desiccant bag in the jar.
In this way, one does not have to use the entire large can of beef stew every meal for 2-3 days in a row. You can also package together, in a single jar, portions of different entrees/veggies/deserts together and have your own complete multi-course meal in a quart jar, with zero waste or loss of taste quality. It’s a kind of homemade MRP– Meal Ready To Prepare. Regards – Bob