PSA: Always Known Your Caliber (300 BLK in 5.56 KaBoom)

Nathan S
by Nathan S

Originally posted on Reddit, one very fortunate shooter survived a catastrophic failure by detonating a 300 BLK in 5.56 firearm. 300 BLK has many advantages, but can have one real disadvantage. It can chamber in a 5.56 firearm under certain circumstances.

Quote from Reddit:

Murphy’s Law struck hard this past weekend where somehow some way a 300BLK round made it from the box on one side of the table, into the mag of another AR on the other table. No one was hurt due to proper PPE. The lower survived with just a broken bolt catch and the upper, as one would expect, is a complete loss.

Always make sure to know your caliber.

Nathan S
Nathan S

One of TFB's resident Jarheads, Nathan now works within the firearms industry. A consecutive Marine rifle and pistol expert, he enjoys local 3-gun, NFA, gunsmithing, MSR's, & high-speed gear. Nathan has traveled to over 30 countries working with US DoD & foreign MoDs.The above post is my opinion and does not reflect the views of any company or organization.

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  • Highhammer Highhammer on Jan 14, 2015

    yikes. once me and friend brought out a new shooter. had a verity of arms out at the range. braked for lunch. the excited new guy made it back to the range before us and we found him loading 7.62x39 in to a 5.56 pmag. i was surprised he was able to fit it in there. thankfully we were able to laugh at his expense instead of making a call to 911.

  • Gizmo Gizmo on Jan 16, 2015

    What's more amazing is someone actually received a Sierra Nevada Arms lower!