Blown up DDM4 (ammo mfg update)

[Shagnasty]

First post guys. long time lurker.

Range rifle had a KB. Customer was using a factory new box of HPR .223 ammunition. Minor wounds to the top of his hand, nearest the thumb. Rifle was running a vert grip and cust. was holding it broom handle fashion.

At the suggestion of a coworker who frequents this place I'm offering up the pictures for a possible analysis of what might have happened.

I forgot to get pictures of the case, but it was split in a similar fashion to the barrel, down to about the portion where a belt would sit on most magnum casings. Nearest we can tell from the evidence is that the round was overcharged. We've all but ruled out the possibility of a squib. Customer was relatively experienced with firearms and didn't say he heard any phut's or puff's and the gun cycled normally on the previous round.

The most interesting part was there was no evidence of damage anywhere else but the barrel. Bolt, receiver, even the DD free float quad rail were untouched. Looks like the fragmentation was just enough to break skin but not enough to damage the aluminum on the HG. Also, we did notice some copper ingrained in the portions where the split occurred on both sides of the split. I'm guessing the round deviated sideways, shredding and destroying itself in process of rubbing copper into the break.

2 more low quality pictures to follow. Sorry, I can not get more photos, as the rifle was shipped back to DD the following day.

[hunt_ak]

Be interesting to see what they say. Did you contact the ammo manufacturer as well?

[Shagnasty]

Be interesting to see what they say. Did you contact the ammo manufacturer as well?

We have. They're working it out now.

[Mauser KAR98K]

What grain/round was the ammo? How new was the weapon?

[SMETNA]

Mind disclosing the name of the ammo manufacturer?

[curt33]

wow that makes me want to do a little resurch and fined out how much preasure a m4 barrel can take. i would like to know how hot that round was. that would scare the shit out of me if that happend at the range. glad to hear he walked away with minor damage insted of major

[BAC]

Squib?


-B

[curt33]

undercharged round. bullet does not have enough gas to clear the barrel. becomes a blockage.

correct me if im wrong though

[skyugo]

undercharged round. bullet does not have enough gas to clear the barrel. becomes a blockage.

correct me if im wrong though

that would be my best guess as well.. I don't think there's enough powder volume in a 5.56 round to pop a barrel like that... (without an obstruction of course... all bets are off with something lodged in the barrel)

[AKDoug]

I've been a reloader and shooter for over 25 years. It would be pretty tough to get that much powder in a 5.56 as long it's the proper powder for the 5.56. It would be possible to do it with the wrong powder. However that's highly unlikely to happen in a factory produced round. Overcharges are far more common in handgun rounds.

A squib will do that and so will a fouled barrel. I haven't been around a squib that cycled the action on an AR. I have been witness to a squib from a 7.62 in an HK 91. The guy didn't recognize the issue, yanked the charging handle to load another round, and kaboom.