Video seems to show falling brass setting off primer. Can it really happen?

tws3b2

tws3b2

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Just watched a youtube video of a guy shooting what looked like a 9mm at a gun range. He was standing in a booth. Counter in front of him, walls on both sides to separate him form other shooters. Targets down range.
On the counter was a patshally open box of ammo. The plastic grid that holds the shells primer up was half out of the box. About half the shells were exposed. Primer up.
The guy fired several rounds down range.
In the video you can see a caseing eject from the gun to the guys left. You can see the caseing fly up, hit the wall and bounce down onto the exposed shells setting one round off. The exposed round explodes right there on the counter.
Looked real to me.
I never would have thought.
Ever see anything like that?
 
About the only way in my imagination is that maybe there was a clump of poorly mixed powder that didn't burn with the initial ignition. That may have fizzled, like a dud firecracker.

Myth buster time. :D
 
kcofohio said:
About the only way in my imagination is that maybe there was a clump of poorly mixed powder that didn't burn with the initial ignition. That may have fizzled, like a dud firecracker.

Myth buster time. :D
Click to expand...
No, I'm talking about the spent caseing falling onto the primer of one of the exposed rounds and setting it off. The spent caseing did not explode. The exposed unfired round in the box exploded.
 
Discussed on other boards, it seems to have been a real event.
There are a good many reports of dropped rounds landing primer first on gravel and going off.
Plus a round being unloaded slipping off the extractor and bringing the primer against the ejector. I have been present for one of those. Don't hold your hand over the ejection port.
 
But, The wall ( in my know nothing opinion) took the force, the momentum, the energy out of the slung ( by the ejector) caseing. So basically (again in my know nothing opinion) all you had was a falling spent caseing. How could a spent caseing falling from 2- 3 feet onto a primer cause it to go off.
Like I said, I never would have thought. Just amazing to me.
"In a I know nothing kind of way."
 
"If" it was real it wasn’t the force that set it off, it was the heat from the freshly fired casing.
Even with that I can only surmise the round that went off must have had a severely preloaded primer to be that sensitive.
I have often carried loose rounds in a pocket or a pouch. Even with them randomly bouncing around I have never had one ignite.
 
Atavar said:
"If" it was real it wasn’t the force that set it off, it was the heat from the freshly fired casing.
Even with that I can only surmise the round that went off must have had a severely preloaded primer to be that sensitive.
I have often carried loose rounds in a pocket or a pouch. Even with them randomly bouncing around I have never had one ignite.
Click to expand...
I don't know about the heat. The round went off the instant the spent caseing touched it. Seems to me it would have taken some time for the heat to transfer from the spent caseing to the primer caseing. Not very likely to me. Just to fast
 
No way you could get enough heat transfer that fast through such a small contact area.

Also, primers aren't that heat sensitive. If they were, we'd be hearing about rounds being chambered in just fired guns cooking off all the time.

Finally, ejected brass shouldn't get hot enough to set off primers even if you could get enough heat transfer. Priming compound (depending on the specific makeup) shouldn't cook off until it gets up in the range of 375F to 500F. This study indicates that ejected pistol brass doesn't get anywhere near 300F.

https://pubmed.ncbi.nlm.nih.gov/20494533/

It does boggle the mind that the primer was set off by impact, but there doesn't appear to be any other reasonable explanation.
 
It is meaningless to speak of probabilities after the event has already occurred.

You have to consider consequences.
Rounds have gone off from hitting the ejector upon unloading. If you have your hand over the ejection port to keep from having to bend over and pick up the cartridge when it fires, it will hurt.
If you let it fall, it might go off from hitting a rock. Will the bits fly far and hard enough to hurt? I doubt it.
 
I think it is very possible. some guns eject like it’s an effort and you get a gentle patter of brass around you. Some of them throw that casing out like it’s an activated hand grenade. Just the right angle + perhaps a sensitive primer (maybe Federal) and I think the momentum of the case head could do it. Luckily it seems such incidents usually don’t result in much more than a fright, since there’s no barrel to retard the bullet’s egress and build pressure.
 
Gotta be about the same odds as hitting a Powerball jackpot. Can it happen? Yes. Hit that primer just so perfectly, and bang. Is it likely? Absolutely not. And without the round being enclosed in a chamber, it's more like a firecracker going off next to you. I'm more worried about what's happening on the road when I drive or if I'm about to run out of dark chocolate....
 
BillTell said:
I'm more worried about what's happening on the road when I drive
Click to expand...
What, you're only worried about what's happening on the road when YOU drive???:D
I love my wife, and as I've mentioned many times on THR, she as into guns, hunting and shooting as I am. But I'd much rather be doing the driving myself when we're "on the road." ;)
 
I don't see why not. Sure, it's a one in a million chance, but someone does eventually win the lottery. I've heard of live cartridges being dropped or thrown and the primer hits just right to discharge the cartridge. Most of the incidents I'm aware of involved a 22 rimfire.

One I was personally aware of. It was 1980 and I was a 1st year teacher. One of my students reached into his jacket pocket and found a single 22 cartridge that he had left in there from a previous hunting trip. Not wanting to bring it into the school he decided to toss it. It landed just right on the parking lot pavement and discharged. No one was injured and there was no damage. The kid was suspended for a few days.
 
I would guess that after the case hit the wall, it was the rotational force of the case spinning that did the work. Imagine the case head (heavier than the open mouth end) acts like the head of a hammer and it spun at just the right frequency for the case head to hit the primer as it landed on the loaded rounds.
 
JohnKSa said:
It does boggle the mind that the primer was set off by impact, but there doesn't appear to be any other reasonable explanation.
Click to expand...


Yep.......thankfully, cartridges detonated unsupported like that are relatively harmless, other than the stain in the pants.
 
Boss told me the story of something like that happening to him years ago. I was always in the back of my mind yea right. No reason to doubt him but it just seemed so far fetched. Sent him a link to the video and he said YES just like that.

I think it is in the group that if it can happen it will happen.

Now with video proof of this happening, what is going to be the outcome? Store all loose ammo in a bag under your station? I am quite sure some knee jerk, or other jerk rules will come about because of this.
 
I've not heard of anyone being injured from something like this and it seems to be a low probability event on top of that. Probably makes sense to close the box of ammunition before you start shooting but I wouldn't think it warrants any more caution than that.
 
I was a Range Officer for our department's night qualifications one year. As one officer was loading his P220 magazine, he dropped a Federal Am. Eagle .45 ACP round that landed primer down on the concrete, ignited and propelled the bullet eight lanes down where it struck another officer in the boot heel (didn't penetrate). If I hadn't witnessed it, I would not have believed the story...but the particular officer that dropped the round was prone to fluke accidents.
 
tws3b2 said:
But, The wall ( in my know nothing opinion) took the force, the momentum, the energy out of the slung ( by the ejector) caseing. So basically (again in my know nothing opinion) all you had was a falling spent caseing. How could a spent caseing falling from 2- 3 feet onto a primer cause it to go off.
Like I said, I never would have thought. Just amazing to me.
"In a I know nothing kind of way."
Click to expand...
i have had brass bouncing off a side wall land on another gun on the table and cutting into the finish( my cz shadow 2) at least 3 times one range session.
 
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