Criterion CORE Series Barrel: 12.5" Carbine Length
  • Criterion CORE Series Barrel: 12.5" Carbine Length

    SKU: CBI12.5

    Headspaced Bolts:

    We recommend having a headspaced bolt in your AR. While it can tighten up the level of accuracy your gun could acheive, for the majority of us (who aren't shooting long distance precision), the more applicable benefit would be on the mechanical side. With a bolt that has been checked to fit your barrel best, the gun can operate smoother, helping components last longer.


    For example, if the bolt doesn't stay locked long enough you can experience "hard extractions" (casing being pried from the chamber before it has "shrank"). This can slow carrier speed and damage extractors, wearing them out sooner rather than later. If the carrier is slowed too much, the bolt may not pick up the next round from the magazine or fail to lock back on an empty magazine. Hard extractions can also result in the extractor prying only a chunk out of the casing's rim, leaving the casing itself in the chamber.


    Will your AR "work" if you don't have a headspaced bolt? Sure. However, if you are going to have/build tools that you may rely on to protect yourself, we believe that properly maintaining them is just as important as learning to use them. We would also encourage folks to add a Headspace Guage Set to their tool chest so that they can check headspace themelves and replace bolts if/when needed.   


    *Drop Down Menu Explained -

    • The Headspaced Bolt option, is the bolt only.
    • If you choose to add the Bolt Carrier Group, this option comes with the aforementioned properly headspaced bolt.
    • Gas Block sold seperately. Below in the "Additional Information" section you will see a block that states "Gas Block Dia.". This is referencing the Gas Block Journal diameter. The journal is the portion of the barrel where the gas block is installed. The CORE Series Barrels have a .625" journal and therefore you will need to use a .625" gas block.


    Criterion's CORE Series barrels are designed with tactical shooters in mind. These barrels are built to address issues with weight distribution, balance, and handling of traditional profiles, while increasing performance through consistent harmonics and uniform heat dissipation.

    The CORE Series feature a modern, continuous taper profile that eliminates steps and harsh variations in diameter. The steel is redistributed where it is needed most: surrounding the chamber. Added weight over the chamber absorbs heat evenly during hard use and moves the balance of the rifle closer to the body for increased control. This is optimal for maintaining balance when used with modern accessories like Low Power Variable Optics (LPVO’s), weapon-mounted lights, suppressors, clip-on night vision devices, and IR lasers; these components boost the capabilities of the rifle, but can hinder the shooter’s performance by increasing front-end weight. The front end of the CORE Series remains light and fast for better handling, balance, and speed.


    The CORE Series 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.



    • Chrome-lined for superior barrel life and corrosion resistance. Our chrome-lining process is the most refined in the industry and will not degrade accuracy.
    • .223 Wylde chamber that is designed to safely and reliably fire both .223 Remington and 5.56 NATO ammunition while increasing accuracy due to more consistent chamber pressures.
    • Honed and hand-lapped rifling produce perfect bore uniformity and a pristine internal finish – aids in barrel cleaning and is paramount for accuracy
    • Finely polished chambers for reliable extraction and feeding
    • Carbine gas system compatible with AR15 carbine length gas tubes
    • Gas hole tuned for proper function with and without suppressor
    • 0.625” Gas Block, dimpled for ease of installation and solid lock-up
    • 1/2×28 TPI muzzle threads compatible with a wide range of muzzle devices and suppressors
    • Precision-machined barrel extension with M4 feed ramps






    CORE Series






    223 Wylde




    6 Groove


    4150 CrMoV


    Chrome-lined, Phosphate


    1.45 lbs


    Recoil Spring / Buffer Recommendations:

     - Spring and Buffer information will be available in the future -