Does Ammo Go Bad? [Shelf Life & Storage Tips]

Is that old box of ammo that you found safe to use? Perhaps so. Ammunition isn't a perishable good - if stored correctly, it can last almost indefinitely. Whether it was stored correctly or not is another matter.

Ammunition isn't like the still-edible 5000-year-old honey found in Egyptian tombs; ready to eat and spread on toast. It has a limited shelf life that depends on factors like where it's stored, exposure to moisture, variation of temperature, exposure to light, whether it was sealed properly, and whether the casing is lead or steel.

Before you fire your weapon, you must determine that you're not using bad ammo. Firing ammunition that has gone bad can be harmful to your gun and dangerous to yourself. This article will show you how to increase the life of your ammo by creating the perfect storage environment.

What's the worst-case scenario for firing old ammunition?

So you've found a box of ammo that you stored and forgot about. The cartridges look reasonable. Sure they're not in mint condition, but they're not rusty, even though you've had them for a long time.

These are the most common mishaps that could occur when you squeeze the trigger:

• Misfire. The primer doesn't ignite the powder. This is probably the most common side effect of old ammunition.
• Explosive crystals magnify the explosive power of the ammo. Explosive crystals form through a chemical process, making the ammo more potent, damaging the firearm when fired.
• Acidic reaction upon firing. This exposes your gun to acid fumes that degrade its workings.
• Jellification. This reduces the performance of the ammunition, and like a damp squib, the bullet may not be expelled upon firing. This obstructs the barrel, making the next round fired into the obstructed barrel extremely dangerous and unpredictable. If you fire your weapon and it makes an uncharacteristic sound, safely unload the gun and run a rod through the barrel to ensure that there isn't a bullet lodged.

What's the shelf life of ammo?

Modern ammo is made to last over a decade (and possibly up to twenty years), provided you stick to proper storage practices.

The usable shelf life of ammo is relative and based on several considerations. These come down to the individual manufacturer's loading methods, quality, and components such as powder, primer type, and sealant.

Steel cased ammo is more prone to rust than brass-cased ammo. Additionally, a bullet with exposed lead is more likely to degrade than a bullet with a full metal jacket.

Ammo manufacturers limit their exposure to liability by being more conservative in their estimation of shelf life (not to mention they will sell more ammo boxes by encouraging more frequent purchases).

Proper storage can make your ammo last longer

The shelf life of your ammunition depends on the conditions you store it in, how you limit exposure to high and low temperature, moisture and other factors.

Any time you take ammunition out of storage, start the clock on the expiry of your ammo. Any ammunition you take out into the field, whether on a hunt or to the range, should be used first.

Try separating ammo that you took out but didn't use from the newer rounds not yet placed into storage. While this ammunition won't immediately degrade to uselessness, it's something to watch over time.

Remember to rotate your ammo, especially for concealed carry firearms

Proper ammunition storage is crucial for firearms you rely on in an emergency, like your concealed carry firearm. Such a gun could go years without being fired. Although most manufacturers recommend not using ammo older than ten years, it's better to be safe than sorry. After a few years, use those older rounds at the first opportunity, maybe getting some practice in at the shooting range.

Tips for storing ammunition to increase lifespan

Keep your ammo in a cool, dry place

This space should have very limited exposure to air, low variance of temperature and low extremes of humidity and moisture. Constant exposure to humidity is the number one cause of ammo degradation, particularly when it comes to corrosion. Guns and ammo love a dry environment, such as inside a specialist pistol case with cutouts for ammo.

Ammunition storage boxes are the best storage option.

A gun case must seal tightly to keep out elements that can damage your ammunition. UK gun cases are watertight, airtight, all-weather, and include desiccants to prevent rust.

Another viable option is to use heavy-duty plastic ammo cans. These are water-resistant, o-ring sealed cases that can store ammo for several years.

Vacuum pack for freshness

If you have a vacuum sealer, this will do a good job of preserving your ammo. If you're sealing it this way, include some silica gel packets to absorb any ambient moisture.

Control the temperature

Whatever container you're storing the ammo in, make sure the temperature is consistent and cool. Extreme heat and cold interact with moisture in the air, and if this seeps into your case or container, the invisible but inevitable chemical reaction will start to damage your ammo. This is especially true in coastal areas where salinity exists.

Go dark

Limit your ammo's exposure to sunlight. Direct OR reflected light can cause degradation over time, so always store your rounds in a dark place.

Avoid oils, solvents or other chemicals

It's possible that these solvents can atmospherically seep into the cartridge and compromise the powder, or cause corrosion on the casing. Avoid storing them in the same general location as your ammo to prevent mishaps.

Don't store ammo in places that shake, rattle, and roll

Storing ammo in places prone to lots of movement, like the trunk of your car, is a bad plan. Cartridges knocking against each other can eventually degrade or suffer damage.

Final thoughts

If you want the best results from your ammo, proper storage is a must. Keep your ammunition in an environment that excludes humidity, moisture, and extremes of temperature, sealed from air currents and other spoiling factors that can compromise the cartridge and alter its chemical composition.

Creating the perfect environment for your weapons and ammunition is an investment every serious gun owner should make. We recommend specialist gun and ammo storage cases, which are ideal whether you store them at home or are on the move.

We hope this article has helped you. As always, drop us a line if you have any queries about the safe storage of guns and ammo.