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Can I shoot 300 BLK through a 556 barrel? — 5 Answers

by Ithaca, from UT, United States Asked on August 7, 2024

Name Rosco Manufacturing 5.56/.300 BLK Bolt Carrier Group (BCG) (4.9)
$140.00 $139.99
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A
Answered by Rosco Customer Service, Manufacturer from RI, United States, on April 17, 2025

NO, that would be extremely dangerous.
All barrels are marked for their specific caliber.

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Answered by Rich C, member, from CT, United States, on March 25, 2025

Ummmm………NO!!!!!!!!!

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A
Answered by AD, guest, from RI, United States, on February 13, 2025

No Absolutely Not

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Answered by Concerned Citizen, member, from PA, United States, on January 28, 2025

Please do not attempt this. 300blk is a 30 caliber round, 5.56/.223 is a 22 caliber round. Your gun will fail catastrophically. That being said, the first rule of firearm safety is to have fun!

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A
Answered by AD, guest, from RI, United States, on December 18, 2024

NO, barrels are specific to the caliber.

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