storing guns and ammo in the attic where it gets real hot

[rustyduck]

in ammo cans good idea?

 

[Gus McCrae]

Though ammo is often stored in hotter places, it's probably not best for the ammo. Why in the attic?

 

[Vanilla Gorilla]

If it is NATO Spec Ammo from Lake City or NATO Surplus you should be ok. It is designed to be stored indefinitely at temps up to 220 degrees. Personally I still wouldn't do it. I don't know the science behind it but I have noted a fairly drastic drop in accuracy in ammo stored at high temps for long periods of time.

 

[mb504]

If you wouldn't be comfortable there, your ammo wouldn't be either.

 

[IfItFliesItDies]

Bad idea. Store it in the air conditioning.

 

[machinedrummer]

Don't do it or you will be sorrrrry. Heavy duty temp and humidity changes is not mans best friend, best friend.

 

[LongGoneDays]

So what about storing a carry pistol & backup mag in a vehicle for 12 hours in the summertime?
I was always told to not worry about it.

 

[RobFMJ]

So what about storing a carry pistol & backup mag in a vehicle for 12 hours in the summertime?
I was always told to not worry about it.

I believe that's under the assumption that you cycle through your carry ammo on a somewhat regular basis. I got no qualms about exposing ammo to highish temps, just not for years on end

 

[Nolacopusmc]

They probably told you a lot of other BS too...

I impressed upon my troops the need to change out their vehicle-carried ammunition every six months at a bare minimum. Very few actually did it, because that required spending their own money; but they were warned of the potential problems with heat and ammo. Also, carrying shotgun shells base-down was discussed.

While I am not aware of any documented heat-related failures with LE ammo carried around in a unit for extended periods, the deleterious effects of high heat on ammunition in general are well known.

The shotgun shell problem was well-documented by Riverside KA PD.

.

AT your leisure, could you elaborate on these two issues? While I was slightly aware of the heat, this is the first i heard of the shotgun issue.

Is that also with modern ammo or was that with the ammo back in your day?

Serious...i am sure there are many here who are unaware of the logic surrounding both.

 

[brichard]

thanks for the insight on the vehicle carried ammo. I've had the same ammo in the truck for at least two years. Probably need to switch it out so it works if i need it!

You are right, a decent round for personal protection does get pricey.

 

[lsu fan]

Heat is a concern but my main concern would be humidity...especially if you want to store your guns in the attic.

 

[hdfinder47]

When I was with STPSO around 1990 someone turned in some old surplus 45ACP that had been stored in Grandpa's attic. I volunteered to dispose of it and out of around 30 rounds, 2 did not ignite. The rest fired fine and with acceptable accuracy.
Whereas that failure rate would not be satisfactory for SD/HD ammo, it did suffice nicely for practice, er, I mean - disposal.
Oh, it was made in 1943. Case looks like steel or aluminum.

 

[Sin-ster]

From my own academic knowledge and research, I've come to find that those worth listening to all basically say the same thing.

As LSP has pointed out, extended heat exposure isn't a good thing-- powder break down and excessive pressures being the primary concern. This means that the question posed by the OP is definitely not a good idea. Also of concern in the attic storage situation are extreme cold temperatures, and increased humidity.

Long term exposure is the problem. A single 12 hour "baking session" is a concern, but almost certainly not going to be a problem. Even a few days of this treatment should not cause serious problems-- again, according to both experienced voices and actual tests that folks have performed. However, an entire month (or summer) in these conditions are likely to result in pressure spikes. LSP's recommendation is consistent with others-- if you can't avoid this scenario, then you should cycle your ammo out frequently.

If you know you will have to leave ammo in a hot vehicle in rare instances, there are steps you can take that actually keep the temperature way down. First and fore most, avoid sunlight-- the dash is not the proper location! The trunk is also a very bad idea, as the temperature is notably hotter than in the passenger compartment. Your best bet is in the floor board behind the front seats.

You are also advised to cover the ammunition with something that will reflect any sunlight that might reach it. This has the added benefit of concealing it from prying eyes. White t-shirts are better than black sweaters-- they refract the light and don't provide much insulation.

I am a firm believer in cycling out your carry ammo frequently, regardless of circumstance. It avoids bullet set back issues, if you're practicing as much as you SHOULD. It allows you some exposure to how your chosen load feels, and ensures that your pistol isn't choking on it-- even after the reliability tests you SHOULD have performed to begin with. And obviously, it ensures that the ammo is fresh and will go bang when you need it most. Typically, if I've left ammo in a hot car and it's been in my gun for a reasonable amount of time, I go ahead and shoot it all up ASAP-- even though the heat exposure was short and I took all the steps to keep it as cool as possible.

Now a story on how silly I can be.

Shooting a match in Poplarville on a ridiculously hot September day, I left a box of Federal 9mm on the seat in my rush to get ready for a stage. (I also left my iPhone right next to it.) Despite cracking the windows, the ammo was literally too hot to touch when I came back to it about an hour later. (The iPhone was locked down to avoid damage.) Fortunately, I had several boxes in my (black) range bag that were MUCH cooler.

Needless to say, that super hot box didn't go to waste-- but I fed it to one of my less favorite (and expensive) guns, just in case there was a problem! (The iPhone made a full recovery.)