CORE Series 300 Blackout AR15 Barrels

The Criterion CORE Series 300 Blackout AR-15 barrel is an ideal pairing for the versatile .300 AAC Blackout cartridge. It helps you handle real-world applications by maintaining exceptional performance and rugged reliability during hard use. These barrels work for you wherever mobility is a priority and performance is essential.

Why CORE Series?

• Continuous taper – eliminates unnecessary steps and harsh variations in diameters
• Added chamber material – absorbs heat evenly during hard use and moves balance closer to the body
• Balanced profile – optimizes balance when shooters use modern accessories such as LVPO's lights, suppressors, clip on night vision devices, and IR lasers
• Lightweight – reduces front-end weight for better handling, balance, and speed
• .223 Wylde chamber – safely and reliably fires both .223 Remington and 5.56 NATO with improved accuracy due to more consistent chamber pressures
• Chrome-lined – improved barrel life and corrosion resistance without degrading accuracy
• Honed - refines bore for superior uniformity to reduce bullet deformation
• Hand-lapped – essential for accuracy and to minimize fouling
• Polished chamber – reliable extraction and feeding
• Precision-machined barrel extension – safe and reliable feeding

More About the 300 AAC Blackout

The .300 AAC Blackout cartridge was designed to shoot .30 caliber bullets from the AR15 while maintaining parts compatibility and standard capacity. It shoots supersonic ammunition with ballistic performance similar to the 7.62 x 39 cartridge, and also accepts heavyweight subsonic ammunition which is ideal for suppressed fire. This cartridge is used in a variety of ways from tactical applications and hunting to competition, self-defense, concealed carry, and range use.

The 8.5" and 10.5” barrels feature a 1:7 twist designed to stabilize a wide range of subsonic and supersonic bullets. If you plan on using a suppressor, it will also ensure subsonic loads do not push beyond the supersonic threshold.

Why Headspace Matters

Purchasing a headspaced bolt is not required. However, Criterion's headspace service guarantees optimal bolt to barrel fitment using premeasured bolts and certified headspace gauges, helping to maximize the performance and function of your build.

Headspace (the critical measurement from the bolt face to the shoulder of the chamber), must be checked for optimal performance and reliability. Proper headspace produces consistent chamber pressures and seating depths which results in increased accuracy and reliability, while reducing wear and tear on internal parts and components.

CORE Series Specs

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