How Hot Is Cook-Off Temperature?

[DougCxx]

What temperature is ammo required to withstand?
For military ammo, there must be an actual requirement on the matter.
For civilian ammo is there some set "standardized" or common temperature, or do different ammo makers set their own temperatures?
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[Phantom Warrior]

No technical info, but as far as I know it's at least a few hundred degrees...

 

[Chipperman]

I dunno about any standards, but each cartridge type must be different.

 

[P95Carry]

In combat situations - I have often wondered with regard to SMG's and LMG's .. even HMG's ..... I mean ... damn, that chamber must get awful hot!!!

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Edit to add ......... on further thought .. I'd guess the potential ''cook-off'' time would be shorter than a given round's time in chamber if on full auto ..... however ...... after a sustained burst (from belt fed) there will still be a round sittin in chamber at ready ... so that could get pretty damn hot.

 

[NukemJim]

From "Understanding firearm ballistics" by Robert A. Rinker pg. 42

"average rifle and pistol cartridge will cook-off at high 200 degrees to low 300 degrees Fahrenheit. The average shot-shell cooks-off a little above that at high 300 degrees F. Average being an important word in that statement. Some may be lower or higher."
(Bold lettering added)

Hope this helps.

NukemJim

 

[c_yeager]

You know, ive often heard about rounds "cooking off" but, honestly ive never seen it happen nor have i MET anyone that has seen it happen with their own eyes. Ive seen glowing gas tubes and smoking handguards but never once a cook off.

 

[Ryder]

There are a few manufacturer who offer Material Safety Data Sheets. I searched primers once figuring them to be more sensitive than gunpowder.

Don't quote me on this, I vagely recall that primers light off at 260°F.

 

[Glockster35]

I had to research this very issue for a project at work a few years ago. I went directly to our Ammo troops, and was told ammunition could be safely stored up to 140 degrees, anything above that might be dangerous.

Of course they couldn't provide where they got this information from, but I felt it was useful for my purposes.

 

[BigG]

Cook Off

P95Carry said:

I have often wondered with regard to SMG's and LMG's ... even HMG's... damn, that chamber must get awful hot!!!

That's why the vast majority of automatic weapons fire from an open bolt. The cartridge is only chambered as a part of the firing sequence.

The HK submachinegun is an exception and the Browning .50 but most MGs/SMGs I'm aware of chamber the cartridge AFTER the trigger is pulled, not before. Upon chambering, the ctg is fired and if the trigger is released the bolt locks back, awaiting the next trigger pull.

 

[P95Carry]

Good point BigG .... now you mention it and I actually stop and think (duh!) .. of course, you're dead right. Even my buddy's Mac 10 is exactly that.

 

[Chipperman]

"Vast Majority" is an overstatement IMO. There are plenty of FA weapons that fire from a closed bolt.

 

[BigG]

I clarified in the next paragraph that by automatic weapons I meant MGs and SMGs, iow dedicated automatic weapons. Not assault rifles like M16 or Kalashnikov which are classified as selective fire. Assault rifles are not built for sustained automatic fire even though folks may use them like that.

So I stand by my statement the vast majority of automatic weapons fire from an open bolt. The HK MP5 is an anomaly as is Ma Deuce.