Recently, we had a heat wave in Southern Utah and there were a string of 100-degree days. Thankfully, I�m a little bit north of Las Vegas so it didn�t get to 110, but it was still extremely hot. When it gets this hot over the summer I often get several questions about storing a gun and ammunition in a car, and if it�s safe to do. Let�s start with storing ammunition first. If you�re using quality factory ammunition then you can store it in your car all summer long and it won�t be a problem. A lot of people believe that if it gets too hot in the car the ammunition will explode and you�ll have the Fourth of July inside your vehicle. But the fact is, it has to be over 400 degrees inside your car in order for the ammunition to �explode.� And if it gets that hot in your car you�re probably not on Earth, but in a place governed by a fellow with horns and a pitchfork. The big problem when it comes to storing ammunition in the car is humidity. If you live on the east coast then you know how tough the humidity is. Walking from your house to your car in the morning can leave you drenched in sweat. But as I mentioned a minute ago, if you�re using quality factory ammunition (which is sealed) you still won�t have a problem. The problem is when people reload their own ammo and they buy inexpensive primers that aren�t sealed. This allows moisture to get in and cause the round not to function. As far as storing a gun in your vehicle, it�s pretty much the same as storing your ammunition. You can store your gun in your vehicle in high temperatures without a problem. However, if you�re storing your gun in your vehicle long-term I would definitely lock it up. When I was a police offer I knew several people who left their guns in their vehicles and thieves broke in and stole the guns. Like ammunition, the major problem with storing your gun in your car is humidity. If you have a 1911, you might find a gun with a lot of rust on it after a summer of sitting in your vehicle. However, if you�re absolutely dead-set on storing your gun and ammunition in your car in the heat a simple solution is to put them in a small cooler. I know a few folks who put them in a cooler and they tell me this solves the problem and they�ve never had an issue with humidity or a rusted gun. Personally though, the only time I leave my gun in the car in the heat is when I�m running an errand to the post office or I have to go to the courthouse or some other place where I can�t bring a gun. Otherwise, I prefer not to leave my gun in my car for extended periods of time (mostly because I don�t want to take the chance of someone stealing it) but obviously, you can do what suits your comfort level.

I can't answer your question. I've never stored guns or ammo in my car. Take the g&a out with me when I go and carry it back when I go in.

Long term storage in heat or cold can effect ammo. Twenty five years ago I bought 2000 rounds of mil-sup Lapua(sp) ammo. First shot the case split from head to neck. Tried several more, same results. Broke down a hundred rounds and found the powder was clumped together and discolored. The exposed lead base was oxidized. Don't know how it was stored before I got it but it was sure affected by something. In this case, I suspect cold and moisture.

I worry more about the affect of high temps on optics.

Also, apparently some car thieves have access to electronic devices that can unlock you doors and bypass the alarm.

Reports are that thrives now have no compulsion against knocking out a window in Wally W or Academy parking lots and taking any visible valuables, if not the vehicle.

If to hot for you to sit in for hours, it to hot for wifes, kids, dogs (especially dogs), guns, ammo, optics. Risk of break ins aside - just for temps thats what I go by.

Change the license plates first.

?

Wood stocks will warp badly.

Got pics?

WE had no choice when shooting competitively. Its rare we dont' have 30 days or more of 100 plus, and at times 100 days like that.

We have stored up to 1000 rounds of ammo, handful of ARs, and 3 spotting scopes, not cheap ones either, in the vehicel at times with no other option.

Plus, we shot em in the heat. The gun got WAY hotter firing rapid fire strings when it was 110 in the shade, but us in the sun, than it would get in the car.

Never found any degradation.

FWIW I've had a box of deer rifle shells in the door of the truck since the truck was new, 01....never had an issue with them though about 2 years ago I quit doing that worrying more about vibration rubbing the deterrent off the powder and changing the burn rate to mcuh faster.

RE wood stocks, and don't mean anything by this, but I just don't have any rifles with wood stocks except one 243 and it only gets out in the winter. IT would not surprise me for the extreme heat to do them in a bit.

I would NEVER keep my bows in the vehicle in the heat, though laminated limbs on compounds are pretty solid these days compared to the 70s/80s.

No pics, but I can assure you that a barrel can get unfloated in a hurry when a wood stocked rifle is left in a hot car around here.

You should not be storing guns and ammo in your auto. There are many places in your home to safely store guns and ammo. I am living in a very small one bedroom apartment while my home is being built. I have six rifles, four hand guns, several hundred rounds of ammo, a reloading setup, powder, bullets, press, dies and all components for reloads. And all is stored, locked and out of sight. Plenty of space under the bed, under and behind the couch, in the back of cabinets, etc. be creative.

I wasn't talking about "storing". I was talking about stopping for lunch.

I've left ammo and guns in hot humvee's and LMTV's for hours in some of the hottest places on Earth.

Well made stuff just plain works...

Crappy stuff...well, use at your own risk...

and there IS a difference...

My truck pistol stays in the console. With extra mag and ammo. Hasbeen

The original poster was. His comment was likely for him, given the elaboration.

To the OP, hot ammo can produce hot loads. Car temps can easily get to 140 degrees some places. Shooting ammo that has risen to that level can be dangerous.

How hot is too hot for a can of bear spray to stay in a vehicle?

It's safe, if theft isn't a worry. Wouldn't treat fine firearms as such, but have left Marlins, Mossberg's and ammo in camper shells or pickups for months/years in Southern Calioto's hot desert inland valleys, many a weekend catching Covina at Salton Sea, or playing at the Colorado River with never a problem.
Not many if any places get hotter than that part of the country.

Don't EVER stick a can of MACE under your pickup seat and forget it's there. May take several years but sooner or later it will wear a hole in the can. Not fun when if finally wears through, and driving down the HWY at speed doesn't help the situation, ask me, I know a idiot that did it

Guns and Ammo is ok in a hot car. Shooting Times, though, is not safe....

I too know an idiot that had bear spray go off in a truck.....

I have never jumped out of a vehilcle so fast!! Really kills the resale value....

Keep your firearm loaded and keep it on your person. The only time is should be in your vehicle is when you are.

Do NOT ever store a Glock in a car!

It will melt like a chocolate bar!

( that's what you guys told me...)

It is not unusual to see on the news around here of an aerosol can exploding inside of a car because of heat. I've had cans of soft drink blow up and spray the drink all over the interior. A guy had a SCUBA tank blow up in his car a few years ago because it got hot. Totaled his car and at least 1 other parked next to it. The police initially investigated it as a bombing.

I don't think ammo or guns are hurt long term because of the heat, but I wouldn't want to have to fire ammo while it is still hot though. It can easily reach 150 degrees inside a parked car, probably a lot more in some situations. Ammo is usually loaded and tested at around 70 degrees. I'd imagine that if shot at 150 degrees or more some could be overpressure and unsafe. After the same ammo cools to a more normal temp I'd think it would be fine.

I buy 12 gauge trap reloads for $40.00 a flat and just keep them in the trunk of my car until I shoot them. I don't think that causes any problems.

In Africa, we always kept rifle ammo in the glove box of the land cruiser and that didn't hurt anything either. People say, though,that some PHs who keep ammo in their hunting cars for years or even decades end up having problems because the powder tends to clump together, reducing velocity. Also cordite, which has not been used for 50 years or so, was very temperature sensitive and pressures could rise if you fired it when hot. this is one reason the old British big bore loads were loaded to low pressures.