JMac Customs X-Series Muzzle Brakes / Suppressor Mounts

    JMac Customs has released their new X-Series of muzzle devices that thanks to the external threads also double as suppressor mounts. In fact, the letter X used as a series designation stands for eXternal thread. The muzzle brake portion of these muzzle devices is similar to the company’s RRD brakes. Currently, there are two models of X-Series muzzle brakes available – RRD-2C X12 and RRD-2C X37. Let’s take a brief look at each of them.

    RRD-2C X12

    JMac Customs X-Series RRD-2C X12 (7)

    The X12 is machined of 17-4ph stainless steel and features a black nitrided surface treatment/finish. It has 1.125″-28 external thread pitch. The available barrel thread pitches and caliber options are as follows: 1/2-28 (7.62/9mm), 1/2-36 (7.62/9mm), 5/8-24 (7.62/9mm), .578-28 (.45). The X12 brake weighs 2.5 oz.

    JMac Customs X-Series RRD-2C X12 (5)

    MSRP of JMac Customs RRD-2C X12 muzzle brake / suppressor mount varies from $109.95 to $119.9 depending on the internal thread pitch.

    RRD-2C X37

    JMac Customs X-Series RRD-2C X37 (4)

    The material and finish of this muzzle device are identical to the previous one. The external thread pitch is 1.375”-24 and the following barrel thread and caliber options are available for the X37: 1/2-28 (7.62/9mm), 5/8-24 (7.62/9mm), 14-1 LH (7.62/9mm), 24-1.5 RH (7.62/9mm), 5/8-24 (.45). The company also notes the following concerning the AK thread pitches: “The 14-1lh, and 24-1.5 use the same “facemount” technology that the DeadAir Wolverine uses to help with thread issues.“. The overall weight of the X37 brake is around 2.9 oz with slight variations depending on the internal thread pitch.

    JMac Customs X-Series RRD-2C X37 (2)

    The MSRP of X37 brakes varies from $119.95 to $134.95. Both the X12 and X37 are currently available for preorder with the estimated date of shipping being November 4.

    As you have probably noticed, the main difference between these two brakes is the external thread size that also determines their dimensions. In the image below, the two brakes are compared with the left column being the X37, and X12 brakes shown on the right side.

    JMac Customs X-Series - X37 on left - X12 on right

    The company has also recently released a blast diverter called BDS-37 (Blast Diversion Shield) which size is kind of tailored to perfectly match the X-Series of muzzle brakes although you can use it with other suppressor mounts too. The price of BDS-37 is $67.95.


    JMac Customs BDS-37 (8)

    JMac Customs BDS-37 blast diverter


    Images from

    Hrachya H

    Managing Editor

    Being a lifelong firearms enthusiast, Hrachya always enjoys studying the history and design of guns and ammunition. He also writes for and
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