TFB Review: Arms Room California Compliant Leviathan Grip

    For people who live in restricted states, you have very limited options to continue to keep and bear arms. Moving is not a realistic option for most, no matter how many times people in free states say to do so. So what options are there? Register or go featureless. Dan, of Arms Room California, noticed the fin grips out on the market and came up with his own version, the Leviathan Grip.

    Photo by Arms Room CA of their Gen 1 Leviathan

    Dan sent his new Gen II Leviathan Grip for review. The original Leviathan Grip was more like a fin with rubber over molding and it only came in black. Gen 1 grips had a slight issue where the webbing of the shooter’s firing hand would rub against the corner of the AR receiver end plate. The Gen II grip was redesigned to avoid this and also now comes in FDE.

    What sets the Leviathan Grip apart from your stereotypical fin grip is that it allows you to wrap your thumb around the grip. It’s not as ergonomic as a regular AR pistol grip but at least you can grab the grip. It is within the CA laws and as long as the webbing of your hand is above the trigger it is ok.

    Here is the Leviathan installed on one of my ARs.

    You can see how the raised section of the Leviathan keeps the webbing of your hand away from the receiver end plate.

    The bottom of the Leviathan has an oval that allows the screw to fit almost any firearm that takes an AR grip.

    When using the grip my middle finger lays across the oval. It is a little bit uncomfortable since the oval has a sharp 90-degree corner to its edge. All you need to do is sand it or bevel it with a deburring tool or knife.

    Shooting with the Leviathan Gen II is actually rather comfortable for a fin grip. I recommend using an ambidextrous safety since you will not be able to engage the safety with your firing hand thumb. The grip repositions my hand a bit an actually makes trigger finger placement more consistent. My index finger has to reach all the way forward to engage the trigger. I cannot misplace my trigger finger and use the crook of my finger.

    I actually tried the Leviathan Gen II on my SCAR 17S first just to see how I would like it. I had to modify the grip to fit the SCAR lower. The raised portion matches the contour of an AR lower receiver so the grip won’t sit flush.

    I used my Work Sharp sharpener. It is basically a mini belt sander and used the roughest belt to quickly grind a groove into the rubber.


    Since the Leviathan was designed around an AR-15 with a mil-spec buffer tube, I am unable to use the Leviathan as intended on my SCAR 17. I cannot wrap my thumb around the grip.

    Gen II Leviathan

    Here is the SCAR17S with a fin grip.

    Strike Industries Fin Grip

    If you go with a Leviathan grip for its thumb wrapping ability you need to choose your stock setup carefully. Pretty much anything other than a buffer tube will not have enough space for your thumb.

    Here is the leviathan on another lower of mine. It has the LAW Tactical folding adapter and you can see it interferes with my thumb negating the benefits of the Leviathan grip.

    The Leviathan works as designed. It is one of the few compliant grips that is molded in FDE and as far as I have seen, it is the only rubber over-molded fin grip. But it is limited to ARs with collapsible stock setups if you want to be able to wrap your thumb around the grip. Make sure you fix your stock so it is is not collapsible. The Leviathan is available for preorder and is $39.99. You can order it in FDE or Black. Go to Arms Room CA for more information.

    Nicholas C

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

    Any questions please email him at [email protected]