Ammo in Hot Car

Ron7624 · June 28, 2012, 05:13 AM

I'm kinda new to the forums, and I'm sure this has been covered, but I can't find hardly any discussion. The only thing I've found is a thread on Concealed Carry Com that basically said, 'ammo is good to 300 degrees and don't worry about it'.
I'm in Houston, and work for a 'no carry' company (as most of them are), so I leave my CC locked in my car all day. The outside temp has hit 100+ for a couple of days already, and my concern is ammo breakdown in the 140+ degree car for most of the day.
I hand load, and I'm betting the primers are the most delicate part of the bullet. I've seen their guts damaged or missing on a few primers over the years.
Anyway, anyone got any info that you can share. I would hate to pull the trigger in my time of need and it go click instead of bang.
I have a clip of factory stuff that I've put in my center console to leave until September and I'll see how they work then.
I'm not sure why this has been bothering me, but it has. So what say you?

rickyrick · June 28, 2012, 07:00 AM

I don't know, but I suggest periodically shooting your carry ammo and replacing it with new ammo.

My rifle ammo stays in the along with my pistol and I just shoot it and replace it whenever I get a chance.

You could have some higher pressures if used while hot

mete · June 28, 2012, 07:41 AM

In the trunk of a white car in the sun , air temerature 70 F , the temperature can be at least 150 F !!
The best you can do is to put gun and ammo in an insulated box. From a cheap styrofoam one to somethong better ! Yes , rotate your ammo.

drail · June 28, 2012, 07:47 AM

150 degree heat is not going to cause your ammo to not fire. With some types of powders the pressure may drop a little but nowhere near the point where it won't fire. It is common in AZ and NM to see USPSA competitors storing their ammo in a cooler so that it will still make Major power levels. A much more serious problem is that you won't be able to hold the gun in your hand. Plastic grips or parts may break down but the ammo will be fine. Stop worrying about it. If this were really a problem then the armies of the U.S., the Brits, and the Germans would have had real problems killing each other in North Africa in WWII. They seemed to do OK.

buckhorn · June 28, 2012, 02:17 PM

Good point drail, ammo in the Middle East has surely seen ambient temps of over 100 degrees and more, sitting inside metal ammo boxes inside metal buildings and never 'cook off'. Imagine how hot the magazines get inside our soldiers bandaliers when they're out in the sun. I've heard of temps up to 130 degrees in the sun in Iraq. Not much better in the shade. In metal containers or magazines, we're probably looking at 150 degrees plus! And I don't think they experienced a high rate of mis-fires, as your example of the desert war in WW2 shows.

Ron7624 · June 28, 2012, 08:41 PM

Thanks for all the replies.
I do shoot off my carry ammo a couple of times a year, but I've never subjected my CC to the constant intense heat that I'm going to this summer. Like I said earlier... I didn't want it to go click instead of bang in a time of need.
Regards all.

Superhouse 15 · June 28, 2012, 09:49 PM

I'm in the middle of an experiment now. I have FMJ, JHP, and some rimfire rounds stored in a black painted ammo can in direct sunlight, in the trunk of my car, in my un-air contitioned garage, and in my air conditioned house. At the end of this hot FL summer I'm going to test them all, I just hope I can find someone local with a chronograph by then.

June 28, 2012, 05:13 AM	#1
Ron7624 Member Join Date: May 18, 2012 Location: Texas Posts: 36	Ammo in Hot Car I'm kinda new to the forums, and I'm sure this has been covered, but I can't find hardly any discussion. The only thing I've found is a thread on Concealed Carry Com that basically said, 'ammo is good to 300 degrees and don't worry about it'. I'm in Houston, and work for a 'no carry' company (as most of them are), so I leave my CC locked in my car all day. The outside temp has hit 100+ for a couple of days already, and my concern is ammo breakdown in the 140+ degree car for most of the day. I hand load, and I'm betting the primers are the most delicate part of the bullet. I've seen their guts damaged or missing on a few primers over the years. Anyway, anyone got any info that you can share. I would hate to pull the trigger in my time of need and it go click instead of bang. I have a clip of factory stuff that I've put in my center console to leave until September and I'll see how they work then. I'm not sure why this has been bothering me, but it has. So what say you?

June 28, 2012, 07:00 AM	#2
rickyrick Senior Member Join Date: March 15, 2010 Posts: 8,238	I don't know, but I suggest periodically shooting your carry ammo and replacing it with new ammo. My rifle ammo stays in the along with my pistol and I just shoot it and replace it whenever I get a chance. You could have some higher pressures if used while hot __________________ Woohoo, I’m back In Texas!!!

June 28, 2012, 07:41 AM	#3
mete Senior Member Join Date: June 14, 2004 Location: NY State Posts: 6,575	In the trunk of a white car in the sun , air temerature 70 F , the temperature can be at least 150 F !! The best you can do is to put gun and ammo in an insulated box. From a cheap styrofoam one to somethong better ! Yes , rotate your ammo. __________________ And Watson , bring your revolver !

June 28, 2012, 07:47 AM	#4
drail Junior member Join Date: February 2, 2008 Posts: 3,150	150 degree heat is not going to cause your ammo to not fire. With some types of powders the pressure may drop a little but nowhere near the point where it won't fire. It is common in AZ and NM to see USPSA competitors storing their ammo in a cooler so that it will still make Major power levels. A much more serious problem is that you won't be able to hold the gun in your hand. Plastic grips or parts may break down but the ammo will be fine. Stop worrying about it. If this were really a problem then the armies of the U.S., the Brits, and the Germans would have had real problems killing each other in North Africa in WWII. They seemed to do OK. Last edited by drail; June 28, 2012 at 07:52 AM.

June 28, 2012, 02:17 PM	#5
buckhorn Senior Member Join Date: May 11, 2012 Location: mid michigan Posts: 196	Good point drail, ammo in the Middle East has surely seen ambient temps of over 100 degrees and more, sitting inside metal ammo boxes inside metal buildings and never 'cook off'. Imagine how hot the magazines get inside our soldiers bandaliers when they're out in the sun. I've heard of temps up to 130 degrees in the sun in Iraq. Not much better in the shade. In metal containers or magazines, we're probably looking at 150 degrees plus! And I don't think they experienced a high rate of mis-fires, as your example of the desert war in WW2 shows.

June 28, 2012, 08:41 PM	#6
Ron7624 Member Join Date: May 18, 2012 Location: Texas Posts: 36	Thanks for all the replies. I do shoot off my carry ammo a couple of times a year, but I've never subjected my CC to the constant intense heat that I'm going to this summer. Like I said earlier... I didn't want it to go click instead of bang in a time of need. Regards all.

June 28, 2012, 09:49 PM	#7
Superhouse 15 Senior Member Join Date: September 13, 2007 Location: Sunny Florida Posts: 844	I'm in the middle of an experiment now. I have FMJ, JHP, and some rimfire rounds stored in a black painted ammo can in direct sunlight, in the trunk of my car, in my un-air contitioned garage, and in my air conditioned house. At the end of this hot FL summer I'm going to test them all, I just hope I can find someone local with a chronograph by then.