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August 21st, 2020

.300 Blackout Fired in .223 Rem — Mistake Is Disasterous

.300 AAC Blackout 300 BLK kaboom accident blowup cartridge failure barrel .223 Rem 5.56
Photos and Facebook post by Tactical Rifle Shooters

Yet another .300 Blackout disaster. Unfortunately, that .300 Blackout cartridge can fit in a .223 Rem chamber. Shooting a .308-caliber bullet in .223 bore is a recipe for disaster.

.300 AAC Blackout 300 BLK kaboom accident blowup cartridge failure barrel .223 Rem 5.56

.300 AAC Blackout 300 BLK kaboom accident blowup cartridge failure barrel .223 Rem 5.56The .300 AAC Blackout aka “300 BLK”, is a compact 30-caliber cartridge designed to work in AR-15 rifles. It has a shorter cartridge case to accommodate the bigger 30-caliber bullet while still fitting in a standard AR-15 magazine. Unfortunately, that’s the danger. A careless shooter can toss a .300 Blackout cartridge in with .223 Rem rounds without noting. And because the case-head size is the same as the .223 Rem (5.56×45) the rifle’s bolt assembly will happily chamber and fire the .300 BLK round. Problem is, that forces a .308 diameter bullet down an undersized .223-caliber bore. Not good!

This images were provided by Tactical Rifle Shooters on Facebook. The message was clear: “Don’t try to run 300 Blackout in your .223/5.56mm. It won’t end well. The problem is identical rifles and identical magazines but different calibers.”

Image from Accurate Shooter Forum. Cutaway shows the jammed .30-Cal bullet:
.300 AAC Blackout 300 BLK kaboom accident blowup cartridge failure barrel .223 Rem 5.56

For those who MUST have a .300 Blackout, here are some things you can do:

1. Use different colored magazines for .300 Blackout vs. .223 Rem.
2. Fit all your uppers with caliber-labeled ejection port covers.
3. Mark .223 Rem upper handguards with the caliber in bright paint.
4. Mark all .300 BLK Rounds with heavy black marker.

.300 AAC Blackout 300 BLK kaboom accident blowup cartridge failure barrel .223 Rem 5.56

Comments by Folks Who Viewed these .300 Blackout Disaster Photos:

“The .300 Blackout is simply a badly-designed round. A properly-designed round would have had a feature in the shape that would have prevented cross loading in the first place.” — D. Santiago

“I almost made that mistake… I had a magazine of 300 BLK inserted in my .223/5.56 all night. Fortunately, I never pulled the trigger. Once I realized the mistake, I almost got ill. [After that incident] I no longer own a 300 BLK.” — B. Welch

“Happened to me hog hunting from a helo. Gun exploded in my face.” — B. Hood

“Fire-forming projectiles [is] so wrong in centerfire!” — M. Stres

“Had some dude come into the store the other day wanting .300 Blackout ammo to shoot in his 5.56 AR. It took 15 minutes of explaining for him to understand you got to have a .300 Blackout Upper!” — R. Williams

Permalink - Articles, Bullets, Brass, Ammo, Gunsmithing, Tech Tip 3 Comments »
July 19th, 2020

Mystery Malfunction and Then Kaboom! What is Your Call?

AR kaboom detonation over charge ammo 3-Gun

What happens when a round goes off unsafely in an AR? Watch this video and see. At about the 00:40 time-mark the shooter has a malfunction (click no bang), with a round. He then removes the magazine, and clears the chamber (we think). On the next round, at 00:53 you hear a “Bang” and see a big puff of smoke coming out of the upper receiver (see photo at right). This has been called a “detonation” by the video-maker, but we’re not 100% sure what happened. What do you guys think? Watch the video carefully, and state your conclusions in the comment section if you wish.

What Caused this Malfunction? Watch Video…

In any event, the shooter is fortunate his upper did not completely fracture, launching shrapnel into his face or other body parts. This could have turned out much worse. Here are screen-shots from the video, showing details of the gun after the accident, along with the recovered brass case, which separated near the case-head.

AR kaboom detonation over charge ammo 3-Gun

AR kaboom detonation over charge ammo 3-Gun

AR kaboom detonation over charge ammo 3-Gun

AR kaboom detonation over charge ammo 3-Gun

AR kaboom detonation over charge ammo 3-Gun

AR kaboom detonation over charge ammo 3-Gun

Permalink - Articles, - Videos, Competition, Tech Tip 6 Comments »