Blew up my AR today. KABOOM!

Thanks for the update Rust, and I'm glad you had the rifle replaced. Bravo to distributor.

From all the details I'll give my .02 cent internet opinion and say option #3 in a previous post on the projectile being forced well back compressing the load and creating sky rocketing pressures.

Different type and size powders become dangerous when compressed. Alot of the big stick slow burning rifle powders don't mind a little crunching to get a long bullet in, but some faster burning ball and flattened ball don't like being all couped up in there with little air around them and getting a fire lit to their azzes.


I posted on another thread last year about a round of Norc223 getting pushed halfway back into the case in our Armalite M15A4.

The BCG didn't go into battery because of the askew round jammed, but if it did, maybe we would have been set up for the same disassemble as your rifle.

The powder from the wonky round looked like a blend of very tiny grained ball and flattened ball. The type and burn rate of this powder I do not know, but it's got me thinking there's something in that bullet push back theory causing compressed and super high fast burn rate. Maybe it was lacking a generous crimp and/ or undersize projectile.

The 9mm Parabellum has been know to do this when using fast powders and getting the projectile pushed back causing compression and bomb like detonations. I've read years back where intensionally compressing the right 9mm round by .030" further into the case spiked chamber pressures from 35,000CUP to 75,000 to 90,000. I don't remember where that article is but in was in a Firearms Repair course I did 30 years ago.


Cheers.
 
Thanks for the update Rust, and I'm glad you had the rifle replaced. Bravo to distributor.

From all the details I'll give my .02 cent internet opinion and say option #3 in a previous post on the projectile being forced well back compressing the load and creating sky rocketing pressures.

Different type and size powders become dangerous when compressed. Alot of the big stick slow burning rifle powders don't mind a little crunching to get a long bullet in, but some faster burning ball and flattened ball don't like being all couped up in there with little air around them and getting a fire lit to their azzes.


I posted on another thread last year about a round of Norc223 getting pushed halfway back into the case in our Armalite M15A4.

The BCG didn't go into battery because of the askew round jammed, but if it did, maybe we would have been set up for the same disassemble as your rifle.

The powder from the wonky round looked like a blend of very tiny grained ball and flattened ball. The type and burn rate of this powder I do not know, but it's got me thinking there's something in that bullet push back theory causing compressed and super high fast burn rate. Maybe it was lacking a generous crimp and/ or undersize projectile.

The 9mm Parabellum has been know to do this when using fast powders and getting the projectile pushed back causing compression and bomb like detonations. I've read years back where intensionally compressing the right 9mm round by .030" further into the case spiked chamber pressures from 35,000CUP to 75,000 to 90,000. I don't remember where that article is but in was in a Firearms Repair course I did 30 years ago.


Cheers.

I had a Norinco round do this as well... in a DDM4V5

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I had a Norinco round do this as well... in a DDM4V5

That can happen with any ammunition in a semiauto if it doesn't have a cannelured bullet and a heavy crimp on it (i.e. most commercial 223 ammo). It's a particularly serious issue for the top round of a magazine that gets chambered multiple times without being fired (e.g. the top round in a magazine used in a duty rifle).

Not sure what would actually happen if you tried to fire this round, but I'm glad you didn't.
 
Ohno, I literally just shared my bad experiences with Norinco ARs (if you can even call them ARs...) on another forum. I will never buy one after experiencing what i have... Save your pennies and buy something worth your hard earned money!
 
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