Out-of-Battery BANG! When Round Fires Before Bolt Fully Closed

As posted in the Calguns.net a few years back, there was a nasty out-of-battery firing incident involving a BOHICA Arms .510 DTC AR15 upper. The cause of the out-of-battery firing is not certain but it appears that the ammo was not sized properly and the firing pin may have been stuck in the extended position. As a result, the round went off before the bolt was closed with the lugs seated. In the process, the bolt handle broke off, as the bolt retracted violently, actually ending up outside the bolt raceway.

The shooter was badly injured, with broken bones and ligament damage to his left hand and tissue damage to his right hand. The shooter was holding the rifle with his left hand near the front of the chamber where a gas vent was located. Gas and shrapnel existed the vent hole causing the severe injuries to the left hand.

From range reports, it appears that the shooter had been struggling to chamber previous rounds, and was having trouble closing the bolt. After talking with one of the rangemasters, a poster on AR15.com reported: “The guy was using new reloads that weren’t exactly fitting well into his chamber. [The shooter] was slamming the bolt handle with his palm trying to get the cases to lock in. The guy was also slamming the bolt forward full force from the rearmost position back and forth trying to ram the cases into chamber in an attempt to squeeze the rounds in so the bolt could close. Finally, on one of the attempts … the possibly stuck firing pin rams into the primer and explodes the round when he slams the bolt forward (zero lug engagement hence the KB) and shooter puts himself into a world of hurt.”

Lessons Learned — Don’t Try to Force Oversize Ammo into a Chamber
By all reports, the shooter’s ammo wasn’t fitting his chamber properly. In an effort to force the ammo into the chamber, he worked the bolt with excessive force. That MAY have caused the firing pin to extend or the hammer to fall without the trigger being pulled. One theory is that the trigger system may have been modified, allowing the hammer to fall from the force of slamming the bolt forward. Others have speculated that the firing pin may have failed to retract because the bolt handle was over-torqued — a safety issue listed in the BOHICA manual.

Whatever caused the out-of-battery firing, it appears that improperly-sized ammo (or a poorly-cut chamber) was the root cause of the problems. If you go to a range and find your bolt does not close easily over the ammo — STOP SHOOTING — don’t try to force the issue. Disaster may result. To paraphrase Johnnie Cochran: “If the ammo doesn’t fit, it’s time to quit”.

Photos by Wildcard, originally posted on Calguns.net.