Hell, I was there…

They say anything that goes on the net will never go away. This is definitely true, In the past week an image of a rifle that suffered a catastrophic failure has gone viral. Again. Unfortunately when photos get shared the original story is lost and there is no context to what the viewer sees. A lot of internet experts have posited various reasons why it failed, most of them completely false. Perhaps the most absurd is that it was caused by firing .300 blackout out of a .223. At the time this occurred in December of 2010, .300 Blackout wasn’t commercially available. In an effort to set the record straight, here’s what occurred

Background

Paul Shanks was part of our shooting team at Cavalry Arms Corporation (since closed, GWACS Armory now produces the CAV-15 MKII and offers service and support on Cavalry Arms manufactured units). He built a lightweight rifle on a CAV-15 MKII polymer receiver with these components:
Timney Trigger
9mm upper with gas tube hole drilled out (no forward assist or brass deflector making it the lightest he could get at the time.)
Young M16 carrier
Compass lake 18″ rifle gas SPR barrel, 1:8 twist 223wylde chamber.
Miculek brake
Clark Custom Carbon Fiber Free Float Tube.

He had used this rifle for some time at local and national level matches. The failure occurred at the December 2010 Phoenix Rod and Gun 3 Gun Match. On the close range rifle stage Paul fired 3 rounds and on the 4th round the failure occurred (interestingly we did find all 4 holes in the paper targets).  Karl Kasarda, who was running the timer, saw Paul’s hat fly off and at first thought it was muzzle blast from his brake that caused it. I was conversing with other shooters when heard an extra loud muzzle report and turned in time to see the rifle fall out of Paul’s hand in pieces.

Paul was visibly shaken. We checked him for injuries and fortunately there was nothing major. He had some small scratches on his face and a fragment from the barrel extension in his inner forearm. He was wearing Oakley Half-Jacket glasses and while there was no visible impact on the glasses, Paul now uses glasses with more coverage for shooting.

The Damage

Cracked barrel extension.  The threaded area of the upper receiver and front lug separated from the upper.

The upper receiver split in half
.

The bolt split right down the middle.  Extractor broke off.

The CAV-15 MKII polymer receiver fractured at multiple points.  We speculated that the lower fracturing like this saved Paul from more severe injury as it gave the over-pressure more room to escape more rapidly.

The bolt carrier also suffered severe structural damage.

The magazine blew out as is typical with catastrophic failures.

The Cause

It wasn’t .300 Blackout in a .223 barrel.  It wasn’t head space.  It wasn’t “firing out of battery”.  It was a binary charge in the cartridge of pistol and rifle powder.  Pistol powder burns at a much more rapid rate than rifle powder.  That created the over-pressure that caused the rifle to fail like this.  Paul had purchased a lot of ammo from a commercial reloader.  They had not sufficiently cleaned out the hoppers when switching from pistol to rifle reloading. Fortunately for the public, Paul had bought the entire lot.  The manufacturer compensated Paul for the damage and the bad ammo.  Four years later I don’t feel the need to name the manufacturer because they took corrective action and Paul was satisfied with how they handled it.

I’m sure this will keep coming up every so often in the cycle of the internet.  Please direct people here for the entire story.  This is a cautionary tale for reloaders, and emphasizes the need to wear quality protective lenses.