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If you’re like most preppers, you’re already a stockpiling pro. You’ve got food, supplies, a bugout bag, the perfect weapons, and a great plan. Chances are high that you’ve also begun stockpiling ammunition like a reality TV hoarder.
Having a million rounds of ammo is great, but without proper storage those potential projectiles will be nothing more than a heap of brass–or worse, an accident waiting to happen.
Over time, heat, moisture, and corrosion can wreak havoc on an ammunition supply. Cartridges can weaken and break, primers can lose their zing, and bullets can even corrode and lose mass, making them a safety hazard to fire. Avoid all these potential risks by using these 9 tips for storing your ammunition.
1. Buy Proper Ammunition
Sometimes the best offense is a good defense. This is certainly the case with proper ammunition storage. Starting out with the right ammo is essential to keeping up your long-term arsenal. There are quality versions and terrible versions of every type of ammunition possible.
Avoid buying extremely cheap ammo. You never know the history of the ammo you buy, and there’s a small chance that extremely cheap ammo is a production reject.
In addition, do not buy ammunition that is already old. Any ammo over 10 years old should be avoided, since you can’t guarantee it was stored properly the whole time. Make sure any ammunition you purchase is completely intact, without any broken seals or ripped boxes. As always, don’t store any ammo that hasn’t been personally inspected by you.
2. Label and Rotate
Storing and using your ammo should be like storing and using any stockpiled perishable items. Label your cases of ammunition with the date you bought them and use the oldest dated rounds first. This will ensure that you never leave an old box of ammo in the back for a long time.
3. Cool Temperatures
The best way to store ammunition is in plastic bags inside ammunition boxes that have a rubber seal (to keep moisture out), and placed in a cool, dark area. Rounds that have been exposed to heat may be defective, and this is what you’re looking to avoid most.
While you probably don’t have to worry about wrecking your ammunition on one hot afternoon–that won’t start to happen until at least 150 degrees–but over time the heat degrades the performance of your rounds. Be sure to find a cool dark place that isn’t also damp, as this defeats the purpose. Humidors are for cigars, dry boxes are for ammo.
4. The Clay Desiccant
The number one killer of ammunition is humidity. Storing your rounds in a damp environment is a surefire way to cause corrosion and powder damage. Fortunately there are many options for avoiding this fate involving the use of desiccants.
A desiccant is anything that absorbs water. Some materials do this chemically, while others do this physically, like the clay desiccant.
Sodium bentonite and calcium bentonite are great clay desiccants that absorb moisture wonderfully. You can purchase these in the form of Desi-Paks, which are safe enough even to use with food. While not the most inexpensive option, clay desiccants are a great way to keep your ammo good to go.
5. Silica Gel Packets
Similar to clay desiccants, and usually even more effective, Silica gel packets also absorb moisture and can be used by dropping packets into your ammo canisters. Silica gel packets can be easily purchased online and are an inexpensive yet reliable way to keep your ammo safe.
Another perk of using Silica gel packets is that you can tell when they need to be switched out. You can get packets that change color when they’ve absorbed as much moisture as possible, letting you know when to replace each packet.
6. The Affordable Option
If you’re in a pinch, or don’t have much time to prepare in a doomsday scenario, you can create a great homemade desiccant out of salt and rice. Uncooked rice will keep your ammo dry in the same way that it absorbs moisture in a jar of sugar.
Adding the salt will also keep the rice from spoiling as quickly. Simply mix some uncooked rice with some salt and tie it up in tissue or a fine mesh cloth.
7. Use Vacuum Sealed Bags
An additional tip for making the most out of your moisture defense is to use vacuum sealed bags. While squeezing the air out of plastic bags will work decently, storing ammo in a vacuum sealed bag is the best way to ensure no air–and therefore no moisture–makes it into the presence of your ammunition.
This is an especially useful tip if you want to store thousands of rounds in one bag. Simply vacuuming out any air is much easier than trying to squeeze air out of a trash bag-sized storage option.
8. Check for Signs of Corrosion Frequently
Be vigilant about your ammunition storage. After packaging up your ammo nicely in vacuum sealed bags with moisture-wicking materials and placing it in a cool, dry place, don’t simply forget about it and hope it will last 40 years. Schedule ammunition checks to make sure your rounds aren’t corroding or becoming exposed to heat.
Using clear plastic in your vacuum sealing is ideal for this, as you don’t have to undo the hard work you did sealing your rounds off from the outside world.
9. Reload Your Ammunition
In reality, the best way to store your ammunition is to avoid it altogether. Using ammo is better than storing ammo, and if you have the know-how and the ability, reloading your ammo is a great way to make sure you always have fresh munitions. If you embark on this endeavor, spare no expense.
Learn the metallurgy involved; what makes bullets weak and strong, what makes them fly faster and slower, and the best methods to use for casting them. Purchase as precise a collection of instruments as possible, because even the smallest variations can impact your shooting experience.
I believe it was in one of the Lee Childs books where it was mentioned that you should never store loaded magazines. Apparently, the spring will eventually falter (we’re talking years here, not months), and if/when you go to use it in a crisis situation, the ammo won’t load.
Can anyone verify this info?
Hi l worked at a Ammo depot for 35 years the ammo rounds are in metal containers. And they are put in a building with the heat on most of the year at a temperature of 90 degrees or more all winter long . The heat is usually off for 2 or 3 months Daniel of the year when the humidity is so high you feel wet when working in the building . We do a test on the rounds that are stored in these conditions . With little or no negative effect on the rounds .
Nice list! Many gun owners fail to realize that their ammunition is susceptible to the elements, but anything with metal must be kept away from moisture and sunlight in order to remain usable. Thanks for sharing!
I like that you mentioned to make sure you label your ammo boxes with the dates on them. That way, you can make sure you don’t leave old ammo unused for too long. That is a really cool idea. I am planning on buying a few guns soon, and I want to make sure I know how to store everything properly. I will keep this in mind, thanks.
I can see the value in ensuring that the ammunition you’re buying really is the right stuff. I can think of fewer things that would make a bad situation worse than realizing that you can’t shoot the bullets you had in storage. It would make sense to me to check out a suppliers reliability before deciding to buy from them so you could know that you were likely to get quality ammo and service from them.
We went to go shoot clay ducks with my uncle last evening and my husband’s shotgun almost exploded. It was so handy to understand that storing ammo in a vacuum sealed bag is the best way to ensure no air–and therefore no moisture–makes it into the presence of your ammunition. When we go to buy more ammo for next week’s outing!
Most of these ideas are useless or even destructive.
Humidity will not harm modern gunpowder. The nitrocellulose is in fact BOILED IN WATER for at least 24 hours during the manufacturing process. It can cause corrosion of bullets and cases, but unless you’re packing your ammo into a sealed container in the middle of a Mississippi summer thunderstorm, there is no need to be sticking desiccant packs, let alone putting (corrosive!) salt, into the ammo can.
Do what the military does: start with good quality recent-manufacture ammunition, put it in a sealed container (in reasonably dry weather) and then LEAVE IT ALONE UNTIL YOU NEED IT. Constantly opening the cans just lets in air that may be full of moisture. Sure, test a sample now and then — every 3 or 5 years is sufficient.
Most importantly, keep it COOL. Heat is the real threat to modern ammunition. Heat causes residual acid in the nitrocellulose to break down the gunpowder. It causes primers to degrade. It speeds up the chemical reactions that cause corrosion. NEVER keep your ammo in the attic or the garage. A basement — even a damp one — that remains cool or even cold year ’round is far better for ammo storage than a garage or attic that bakes your ammo by day for months on end in the summer.
Let the experts do it,buy battle packs or cans (nitrogen purged?). Store it like you use it (stripper clips, or magazine quantity, also makes inventory simple ).
30 round mags make 30 round packages. Date them seal them in seal a meal plastic. Works great.
If using #6, add bay leaves to the rice, not salt. Salt is a corrosive
On #7, do not place your ammo under vacuum. Only draw the air out. I use a food saver and only operate the vacuum until the air is evacuated.
Why?
Over time, that vacuum will draw air out of the rounds. When opened, the ammo will slowly draw air back into the cartridge to equalize. This is fine if that air is dry but if you’re in a damp environment or have solvents present, it’s not good.
Load it dry, keep it dry and cool and do not place under vacuum. I even put dessicant in my powder containers and my powder measure hopper during loading.