Ammo Storage Question

[knayrb]

So I had a good find this past weekend. I was cleaning my garage and found a 1000 round case of 5.56mm and another 1000 round case of 9mm. I totally forgot about them. I now remember buying them in the winter about 3 years ago and put them up out of the way. These were to be my emergency prep and bartering ammo. The ammo is about 9 feet high up on a garage shelf that gets probably 120+ in the summer and 32- in the winter. Both calibers are FMJ American Eagle with brass cases.

I was reading that the most damaging thing to ammo is moisture and here in Utah we have very little of that. In the garage I could dig them out easier if a disaster happened. Also up high there is little risk of water damage from a broke pipe during said disaster. What condition do you think the ammo is in baking and freezing for 3 years? Is it fine to leave it there or should I store them under the stairs in the basement where it's cooler?

[Hawk87]

I would put it in a cool dry place, but I would guess they are fine where they are.

[AlanM]

Your garage gets to -32°F????
I just did a quick search and found a record low temperature for Sandy, UT in January of -15°F.
The average low temperature for the year bottoms out at about +20°F there.

Sorry, I'm a numb3rs nut.

[Snurd]

THAT'S where I left my case of 9mm.

[dewittdj]

I'd consider replacing it with new, storing the new, and gradually shooting up the old, temperature cycled ammo.

[dewittdj]

Your garage gets to -32°F????
I just did a quick search and found a record low temperature for Sandy, UT in January of -15°F.
The average low temperature for the year bottoms out at about +20°F there.
Sorry, I'm a numb3rs nut.

Yo! Numb3r nut... almost wrote numb nut but that's different, considering 32- and -32 are not the same. I believe there's about 64 degrees difference between the two.

I believe he was citing a range between +120 and 32 with a dash to denote the end of the range instead of a semi-colon (;).

[knayrb]

Your garage gets to -32°F????
I just did a quick search and found a record low temperature for Sandy, UT in January of -15°F.
The average low temperature for the year bottoms out at about +20°F there.
Sorry, I'm a numb3rs nut.

Yo! Numb3r nut... almost wrote numb nut but that's different, considering 32- and -32 are not the same. I believe there's about 64 degrees difference between the two.

I believe he was citing a range between +120 and 32 with a dash to denote the end of the range instead of a semi-colon (;).

It was a rough guess. I meant 32 degrees or less. Kind of like 40 days and 40 nights = a long time. The point is that it get very hot and very cold.

[Ruminus]

I'd say just go ahead and get some fresh rounds, and I'll take those questionable ones off your hands, no charge.

[UtahJarhead]

The rounds should be fine. Heat shouldn't bother them and neither should the 3 cycles of temperature changes. The worry would be winters since the humidity in Utah rises, but if they're factory ammo, I doubt that would be an issue. Suggestion: Surplus ammo cans, particularly of the .50 cal variety. Waterproof, decently large, and perfect for storage.

[AlanM]

It was a rough guess. I meant 32 degrees or less. Kind of like 40 days and 40 nights = a long time. The point is that it get very hot and very cold.

I guess my post didn't come off as a friendly ribbing as I meant it to be.
Makes sense now that you clarified it.

As to your original question, I agree with the others, the ammo is most probably good to go.

Also, I've found that ever since 2004 when I got my first concealed carry license (in Ohio) I've become much more tolerant of annoying, immature people both in person and on line. I now just tend to ignore them rather than waste my time and energy slapping them down.
Over the last 65 years I've observed several times that time wounds all heels.

[FrankenHollow]

Each component in a metallic cartridge has different enemies.

Brass cartridge case: Ammonia, salts, moisture. Corroded casings are a very bad thing.
Copper-jacketed or copper-plated bullet: Ammonia, salts, moisture.
Anything attacking either of the above is likely to cause the bullet and casing to be partially 'welded' together. This can cause very nasty problems, when fired.
If you have green, black, or brown fuzz, there's a problem.

Steel cartridge case: Moisture, salts, dissimilar metals.
Steel-jacketed bullet: Moisture, salts, dissimilar metals.
Like the copper-containing items above, the steel components can become 'rusted' together and cause serious problems. Letting them sit in contact with dissimilar metals, even in moisture-free environments, can cause galvanic corrosion (this also applies to letting their container touch dissimilar metals, if storing the steel ammo in an ammo can). The up side.... it's easy to spot problems with steel components.

Lead bullets: Humidity swings, heat.
Lead corrodes over time. Humidity and temperature swings can accelerate the process. Lead oxide(s) are toxic, if inhaled or ingested. Handling of corroded lead should not be done without proper safety precautions. The ammunition should not be fired, unless the corrosion has been removed.
Heat can lead to the lubricants on lead bullets melting off of the bullets, or out of the lube grooves. This can cause a big mess and/or powder contamination (squibs, hang-fires, etc), and the lack of lubricant can lead to severe lead deposits in the barrel of a firearm.

Primers: Moisture, temperature swings.
The biggest enemy is moisture/humidity. It won't out-right kill the primers, just by being exposed to high humidity for extended periods of time; but it does cause a slow degradation of the priming compound. Eventually, you can have hang-fire situations, poor ignition, squibs (primer "pops", but doesn't have enough energy to ignite the powder), or out-right duds. This usually isn't a problem, unless the ammunition is seriously old, or has been severely neglected.

Powder: Moisture, temperature swings.
Modern powders will degrade when exposed to humid conditions. What, exactly, the end result will be, is hard to predict. The moisture in the powder lets the volatile compounds migrate to the surface of the granules, completely changing the way the powder will react when ignited. Sometimes, they "flash and fizzle" by being rather non-energetic. Other times, they really go out with a bang, by being much more energetic than originally intended. Unless you store your ammo next to a shower or hot tub, this shouldn't be a problem in Utah.
Temperature swings are smokeless powder's biggest enemy, in loaded ammunition. Temperature swings also cause a migration of volatile compounds in powder granules. In addition, high temperatures accelerate the natural degradation of the compounds in the powder.


Unless you see signs of corrosion, it should be perfectly fine. But.... get that ammunition out of the garage, and into a location that doesn't see such radical temperature swings (or the humidity swings). If your house has a swamp cooler, avoid areas that get air (and humidity) directly from it, as well.

[ian husford]

It is very obvious that your ammo is junk and you need to have me come out and pick it up and at a substantial cost to you so that I may dispose of it properly!
Of course the only proper way to dispose of it is to shoot it...right?


OK...the ammo should be good and to follow the advise given so far.

ian

[faydee]

It was a rough guess. I meant 32 degrees or less. Kind of like 40 days and 40 nights = a long time. The point is that it get very hot and very cold.

I guess my post didn't come off as a friendly ribbing as I meant it to be.
Makes sense now that you clarified it.

As to your original question, I agree with the others, the ammo is most probably good to go.

Also, I've found that ever since 2004 when I got my first concealed carry license (in Ohio) I've become much more tolerant of annoying, immature people both in person and on line. I now just tend to ignore them rather than waste my time and energy slapping them down.
Over the last 65 years I've observed several times that time wounds all heels.

i have to say this here Alan... did you know you have a raccoon on your shoulder?

[Sam Fidler]

I have been working in Iraq for about 5 years not where the summer days regularly hold at 120 and temps inside dark Suburbans are much higher. Ammo stored in these extremely hot conditions for many years have fired without failure. We have been using this old ammo over the past few months in our quarterly quals without any noticeable effect in accuracy. I say, if it doesn't show excessive signs of corrosion, shoot it.

[AlanM]

i have to say this here Alan... did you know you have a raccoon on your shoulder?

Do you REALLY want me to highjack this thread with an off topic discourse on the trials, and tribulations of raising and living with a raccoon?
We had Bert, the raccoon, for a little over a year. I bought him from a breeder when he was not quite weaned. That was 9 years ago. I had to get a Ohio state license to keep him.