Rip Your Favorite Stock with CMMG Fastback Receiver Extension

    CMMG Fastback Receiver Extension (1)

    CMMG RipStock system allows quickly deploying the collapsed AR-15 stock to a preset length in a matter of just pulling the stock back, without a need to press a lever or button to unlock it first. The core of the RipStock system is the Fastback Receiver Extension that thanks to the shape of the stock lock pin recesses allows this ratcheting function. So the Fastback Receiver Extension is not a new product per se. However, up until now, it has been available as part of CMMG firearms or in a kit along with a stock, castle nut, endplate, buffer and buffer spring. Well, now you can buy the Fastback Receiver Extension separately and use it with the stock of your choice.

    CMMG Fastback Receiver Extension (2)

    Note in the above-embedded image that the rearward-facing walls of the stock lock pin recesses are angled while the front walls are straight. This design allows ripping the stock back without the need to unlock it first, yet it doesn’t let the stock collapse back when it is shouldered until the user presses the unlocking lever/button to collapse it. In order to set the length that you want the stock to stop at when pulled back, you need to install the provided indexing screw in one of the five threaded holes located between the lock pin recesses. Overall, there are 6 length positions on the Fastback Receiver Extension. This is a mil-spec buffer tube, it’s made of aluminum and has a hard coat anodized finish.

    Here is the video announcement of the availability of Fastback Receiver Extension as a separate component.

    The CMMG Fastback Receiver Extension is listed on the company’s website at an MSRP of $59.95.

    Do you think this quick deploy stock design is the greatest thing since sliced bread or would you rather stick to using standard adjustable stocks? Sound off in the comments section.

    Images by CMMG Inc,

    Hrachya H

    Being a lifelong firearms enthusiast, Hrachya always enjoys studying design, technology and history of guns and ammunition. His knowledge of Russian allows him to translate and make Russian/Soviet/Combloc small arms related information available for the English speaking audience. Hrachya also writes for
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