Hot Cars: Hard on ammo and polymer frames?

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Ben86

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Do the rather obscene temperatures in locked cars during the day have a considerable adverse effect on polymer framed guns and the ammo inside of them? I keep mine under the seat in a safe, so it is out of direct sunlight. But, it sure does get warm. I have a feeling it doesn't, but I'd like to ask anyway.
 
...however...hot cars can be bad for kydex holsters. I left a blade-tech in the glove box of a car once and it began to lose it's form and lost all retention/tightness. Blade-tech took care of me (great company), but I learned the lesson.
 
...however...hot cars can be bad for kydex holsters.
Kydex is specifically made to soften at relatively low temperatures so it can be easily molded, but the polymers used in gun frames--in fact, most polymers--are far more temperature resistant.

As long as you can pick up the gun without being burned you're good to go. The figures I've seen indicate that it takes temperatures that are 150-160 degrees above the boiling point of water to soften/damage a polymer frame and the interior of a car is not going to get anywhere near that hot unless it's on fire.

What I don't understand about this question is that it's always asked as if the presence of plastic items in the interior of a vehicle is some kind of an anomaly--an oddity or an unusual occurrence. Most (all?) cars I've been in in the last few years had a large number of plastic parts in the interior. Pretty much anything in the interior of the cars that wasn't cloth or leather was made of plastic.

I guess what I'm saying is this: It seems odd to me that people would worry that a polymer/plastic gun frame might be compromised by the heat of a car interior when none of the other myriad plastic parts in the car interior seem to be adversely affected.
 
If you're loaded with cast bullets that have a poor lube on them, the lube can melt off the bullet and degrade the powder. But I don't know of many folks who keep polymer pistols loaded with those.
 
What I don't understand about this question is that it's always asked as if the presence of plastic items in the interior of a vehicle is some kind of an anomaly--an oddity or an unusual occurrence. Most (all?) cars I've been in in the last few years had a large number of plastic parts in the interior. Pretty much anything in the interior of the cars that wasn't cloth or leather was made of plastic.

I guess what I'm saying is this: It seems odd to me that people would worry that a polymer/plastic gun frame might be compromised by the heat of a car interior when none of the other myriad plastic parts in the car interior seem to be adversely affected.

John, this reminds me of a young lady who asked a Home Depot associate if the drain cleaner solution she was considering would be safe for her plastic (PVC) plumbing pipes. He replied: "Ma'am, it's in a plastic bottle."
 
Seems to me a polymer frame gun that can take the temperatures of being fired for a few hours at the range would handle being in a hot car. Just my .02.
 
Bullet lube can melt out of the lube grooves in high temps. I would keep them in a box that keeps the bullets pointed down if you must leave them in a hot car. I had one maker tell me his lube would never melt like that. He was wrong.

Illinois State Police used the Silver Tip 9mm ammo when it first came out. It had an aluminum jacket that expanded well but required bullet lube and groove. It was found to degrade the powder and reduce the velocity. Winchester changed the jacket. I think the 32 ACP Silvertip is the only one left with the aluminum jacket and it has a good record for 32 ACP. (No lube)

Jacketed ammo should be no problem. You should change your carry ammo at regular intervals. I get new stuff every six months or so.
 
Hhmmm....Well, Kahr, Glock, and some of the other manufacturers had problems early on with polymer frames warping in hot, closed vehicles. I guess they got the problems worked out; I haven't heard of recent problems. Ammunition...shouldn't be a problem with rounds cooking-off, but some of the older, sealed, military primers might degrade to the point of not igniting the powder charge--Patrice
 
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Patrice ...

I have never heard of Kahr or Glock having those problems. But then again I usually think steel guns in the case of Kahr specifically.
In essence: Unless you burn yourself on the firearms and you are using really really badd ammo I would not worry about it.
 
Overheating can affect the pressure curve of ammunition causing a spike.
Pistol ammo is not so greatly affected but I would be leery of leaving stuff like .300 Weatherby or .50 Browning in a super heated trunk or out in direct sunlight on a hot day for any length of time.

Unless you live next to an active volcano, guns stored in a vehicle and out of direct sunlight will not become too hot to hold but will get too hot to hold much quicker from shooting than a cool to the touch firearm.

Kevlar gloves are an asset to hot weather shooting.
 
Hhmmm....Well, Kahr, Glock, and some of the other manufacturers had problems early on with polymer frames warping in hot, closed vehicles.
Not trying to be unpleasant, but this statement is unlikely to be true for a number of reasons which are easily verified and should be more or less common knowledge.

Let's start with Glock.

1. As far as I know, Glock hasn't changed their polymer recipe from day one. I have never heard any credible evidence to support the idea.

2. Glock was making polymer items for the military (knives & shovels with polymer handles) and for other purposes for approximately 20 years before they started making polymer firearms. It seems highly unlikely that with more than 2 decades of experience with manufacturing polymer products they would have "teething" issues due to not understanding the effects of heat on polymer when they finally did get into the firearms business.

Now Kahr.

Kahr was founded more than 10 years after Glock started making polymer firearms. That means "early on" for Kahr would have been something like 13 years into the firearms making business for Glock and something like 32 years after Glock started making polymer products. It doesn't make sense to think that Kahr wouldn't have made use of known issues with polymer heat issues given that they got into the business of firearms long after Glock and others had worked the kinks out.

Finally Nylon.

Nylon (Glock frames are a nylon "alloy") was invented in 1935. So Glock started making nylon framed guns about 50 years after the invention of nylon. But you would have us believe that half a century after Nylon came into use that the effects of heat on Nylon still weren't understood? Kind of a stretch, don't you think?
 
I had a feeling this was a concern of an overly worryful imagination. Thanks for the assurance.

Interesting info JohnKSa.

I'd also like to add that I generally think locking a gun in a car should be done as little as possible because of the increased likelihood of theft, and the decreased usefulness of the gun to you when you exit the vehicle. I try to do it as little as possible but, there are times when my carry gun just can't come with me.
 
Polymer guns/ammo, not a problem. I was worried about this at one time, and did some research. Lots of info out there, i.e. the link WEG posted about ammo was a good read. So unless your car gets up to around 400 degrees, you dont have anything to worry about. If it does, your dash, steering wheel and all of your plastic trim pieces will be a problem too!

On another note, if you own a pair of Crocs (shoes) don't leave them in a hot car, they'll shrink!
 
I do not advocate leaving FIREARMS in car's PERIOD~! As it makes
an easy grab for breaking and entering type thieves. ALWAYS keep the weapon
on your person; or locked in a "lock box" inside of a business. The old saying,
"give a criminal a GUN; and he damn sure will take it" holds so ever true here~! :( :fire:
 
Ala Dan said:
I do not advocate leaving FIREARMS in car's PERIOD

I wholeheartedly agree. However there are times when I have too, as much as I don't like it.
 
As others have stated, I would worry more about people breaking into the car and taking it. I've left a G21SF in my glove box for an entire afternoon parked right under the roasting Florida sun. It was pretty hot, but not hot enough to change the shape or anything.
 
While a few plastics may be affected by the interior of a hot car, notice how much of the interior IS plastic?

Nylon (of various types) is common for 'plastic' pistols (the manufacturers are notably tight lipped about the exact composition)..

It is not near the damage level in a car that is not on fire (melting points above 400 F are not uncommon).
 
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