Friday Night Lights: OPS-Core AMP Arm Upgrades And Modifications

    Earpro upgrades

    When night vision is worn on the head, the helmet is the best option. Sure there are other options like skull crushers and night caps, but for the most part, night vision shooters use a helmet. The night vision helmet is a platform to carry accessories. Check out my helmet safety accessory article. Aside from positioning and holding your NODs (Night Observation Devices) over your face, they are great for holding ear pro. One set of helmet mount is the OPS-CORE AMP arms. They are a vast improvement over other forms of ear pro mounts but you don’t need to have OPS-CORE AMP headsets to use them. Here are some AMP arm upgrades and modifications for your night vision helmet.

    OPS-CORE RACs x AMP Helmet Rail Mount

    This isn’t really an AMP arm upgrade but for those of you who spent a pretty coin on OPS-CORE RACs can upgrade them. As simple ear pro upgrades go, this is the easiest. You are swapping the stock RAC helmet mount arms for the AMP Helmet rail mount kit. The AMP kit retails for just under $100. This kit is to allow you to switch from AMP headset to helmet mounted. The RACs do not have this quick change ability as the ear cups are bolted to the arms. However, this does not mean your RACs are obsolete. The RACs were original designed as Rail Attached Communications. And while they do have their own rail mount, it is not the best. I’ve heard from some shooters that the spring tension in the RAC arms is insufficient.

    They said that the ear cups open up under pressure from situations like door breaching with explosives. The Peltor ones do the same thing. Other people have claimed that the RAC arms are not that robust and are prone to breaking. When the arm swings open there are three detent positions. You have to press a plunger to release them so they close back onto your head. The AMP versions are simplified. They have dual springs and only lock open when they are 90 degrees from the side of the helmet. They are a force to overcome design so you just need to push them open or closed. When opened it gives you a tactical Mickey Mouse look.

    So how do you upgrade your RACs? Easy. You just remove the screw that holds the RAC ear cup to the RAC arm. Then screw the AMP helmet rail mount kit arms to the RAC ear cups. Done.

    MTEK AMP/RAC Mount Modification

    If you were paying attention earlier, I had my RACs mounted to an MTEK FLUX. The RAC and AMP rail mounts are designed for OPS-CORE ARC rail. However, there is an easy modification you can do to make to the AMP arm mount MTEK FLUX compatible.

    The MTEK FLUX uses MLOK slots instead of the dovetail rail design that OPS-CORE does. But you can modify them to mount to the MTEK rails. The modification just requires an MLOK screw and T-nut.

    If you look at the photos above and below, there is a metal washer under the screw head. This is from the AMP arm rail kit. I had to widen the inner diameter of the washer to fit the thicker Magpul M-LOK screw.

    So all you need to do is unscrew the ARC rail dovetail from the AMP arm and screw in the Magpul M-LOK screw and T-nut. I used a Magpul M-LOK screw since it has that yellow thread locker on it from factory. This helps keep the screw from backing out when you spin the AMP arm up and down.


    Non OPS-CORE Ear Pro With AMP Arm Upgrades

    However all of the AMP arm upgrades so far required some form of OPS-CORE headset. But people have taken it upon themselves to modify their existing ear pro to work with the AMP arm rail kit.

    Big thanks to Stephen T. for sending these in and teaching me how to do this modification. He modified Peltor 6S ear cups to work with the AMP arm clip.

    The modification is permanent for the Peltor ear pro. You remove the headband and clips. Then cut off the posts that stick out the side of the ear pro.

    Photo by Stephen T.

    Photo by Stephen T.

    Next, you want to drill a pocket where the posts used to be. This is where the AMP arm clip will click onto the ear cups. You will also need to sand/file away some material from the cup to make room for the clip. See the pictures below.

    Photo by Stephen T.

    With the material removed from the ear cup, you should be able to attach the AMP arm clip to the Peltor 6S.

    While the Peltor 6S lacks the 3D audio and NMFI earplug compatibility, you do get similar function and ear protection with the modified Peltor 6S at a fraction of the cost for the OPS-CORE AMP.

    The best part is that since the modified Peltor 6S are not glued to the AMP Arm clips, you could possibly use the AMP headset to wear the Peltor 6S without needing a helmet. Another benefit is since the Peltor 6S are independently powered, there are no wires spanning between the two ear muffs.


    AMP Arm Final Thoughts

    While the AMP arms cost almost twice as much as the Peltor 6S, you can use other headsets. A friend modified a set of MSA Sordins and epoxied the AMP arm clips to the earmuffs. The AMP arms are a better solution to helmet-mounted ear pro. They use up a relatively unused section of helmet rail, Other forms of helmet mounts use the horizontal section of ARC rail leaving you will very little space left.  In the photo above, I was able to mount my ear pro and a Princeton Tec Charge Pro helmet light on the rail.  Hopefully, you may have found these DIY modifications helpful or perhaps inspire you to modify your night vision setup.

    Nicholas C

    Steadicam Gun Operator
    Night Vision & Thermal Aficionado
    Flashlight/Laser Enthusiast
    USPSA competitor

    Any questions please email him at [email protected]