Ammo Cooking off in a House Fire

[AJ Dual]

There's a small chance that fragments from exploding ammunition would be injurious, but testing (such as the American Rifleman article referenced above) has shown that the majorithy of ammunition will just burst in place.

For the minority that does go flying, the bullet is usualy heavier than the case, so the case gets thrown farther, or the primer pops out. The majority of flying pieces are moving at 300fps or less, and standard firefighting gear is sufficient protection from those fragments.

 

[Ben Shepherd]

Not fire caused, but same situation/result-
At an outdoor IDPA match a couple years ago, while we were at the table loading mags for the next stage, my bro-in-law had a 40 S&W round slip over the magazine lips. Lit right on the primer on a piece of gravel, which set it off.

One guy in our group about 15 ft. away had the slug come back down and hit him base first in the back of the neck. He was leaned over at the time, so it was a direct strike. We new it was base first by the red mark it left.

A piece of the case hit me in the shin. Bled like hell. Thought it had just sliced me on the way past due to the angle I was standing and judging by the hole in my pants. Turns out we were wrong.

A year later I dug about 1/3 of a 40 S&w case out from under the skin of my shin. It had taken a year to work its way to the surface. I was lucky, I guess.

 

[mpmarty]

I have no experience as grand as a house or shop fire but last winter I dumped the contents of a small cardboard box that I'd used as a trash can in my shop for used cleaning patches and that sort of combustible into my woodstove. I had forgotten some discarded .40 S&W rounds. I went into the kitchen and soon heard some loud "pops" and went out to the shop to find the front of my woodstove door shot out, it had been tempered glass and there were two distinct bullet holes in it. Slugs found across the shop on the floor, brass was still in the stove.

 

[AZ Jeff]

Major Julian Hatcher did experiments on uncontained rounds cooking off in his book "Hatchers' Notebook" back in the 1930's. The experiments concluded that loose rounds (unchambered) igniting pose MINIMAL risk to anyone in proximity.

 

[simon]

Hmmm...Years ago, a house in LA caught fire and there were lots of ammo inside. When it started cooking off, the fire-fighters left and let the house burn down. Now I think its LAFD policy to let a structure burn rather than try to save it to protect the firemans lives.
This may or may not be true, just something I heard.

 

[DF357]

The moral of those stories are if the cartridge isn't contained by a chamber or barrel, the gases from the burning powder are quickly dissipated on all sides of the bullet at once when it leaves the case. Since it can't build up pressure, it can't have any velocity.

I wish people would not make blanket statements like this.

AMMO CAN EXPLODE AND SERIOUSLY WOUND/KILL YOU !!

My son was sitting around a campfire. A 'friend' threw a .22 round in the fire. Son raised a coke can to his mouth and screamed. His hand was bleeding badly.

The .22 round hit his finger with enough force to take a large chunk of meat off of his finger and splinter the bone. His hand was in front of his eye when he was hit. If he had not taken that sip of soda when he did, the round would have either entered his eye or forehead. It had enough power to shatter his finger so it most likely would have penetrated his skull. He still has metal chunks embedded in his finger bones.

I repeat:
AMMO CAN EXPLODE AND SERIOUSLY WOUND/KILL YOU !!

 

[AZ Jeff]

When Hatcher did his experiments, he concluded the most dangerous round was the .22 rimfire family. This was because the cartridge cases are so thin, they tend to rupture in a way that creates tiny brass slivers that become projectiles, resulting in injuries due to the thin brass shrapnel

 

[shortydog]

I wish people would not make blanket statements like this.

AMMO CAN EXPLODE AND SERIOUSLY WOUND/KILL YOU !!

My son was sitting around a campfire. A 'friend' threw a .22 round in the fire. Son raised a coke can to his mouth and screamed. His hand was bleeding badly.

The .22 round hit his finger with enough force to take a large chunk of meat off of his finger and splinter the bone. His hand was in front of his eye when he was hit. If he had not taken that sip of soda when he did, the round would have either entered his eye or forehead. It had enough power to shatter his finger so it most likely would have penetrated his skull. He still has metal chunks embedded in his finger bones.

I repeat:
AMMO CAN EXPLODE AND SERIOUSLY WOUND/KILL YOU !!

 

[mpthole]

I had read/heard, like most posters here, that when ammo cooks off it just kind of pffffts out and there is minimal risk. Well, this spring we were doing some construction at the club and decided to burn some of the scrap material. We just picked a spot that was convient - never really thought anything of it - except that there were a few live rounds on the ground (it was dark at the time). While the fire was burning we heard a loud pop and then a "thwack" kind of noise. The next day my buddy's Tahoe had a huge dent in the door and on the ground was .45 slug with black paint on it!

Maybe wouldn't have killed anyone, but it sure would have hurt like hell!

 

[clt46910]

Many years ago, when I use to do a lot of hunting and camping. My partner and I, as a joke, would throw loose rounds into the fire to scare new members of our pack. This was everything from 30-06, down to .22's. They would pop and make a big shower of sparks in the fire. We did have a couple primers pop out of the fire over the years, but they never had any force to them. I got hit once but just more like a twig falling out of a tree hitting me. No force at all.

Now contained in a sealed box, like any expanding gas, will make a big explosion. Anything within the box can be propelled with a lot of force.