Coat Hanger Machine Gun DIAS (Drop In Auto Sear)

    This string is a registered machine gun.

    Some of you may or may not know of the infamous “shoe string machine gun”. A piece of string can be tied to the charging handle of an MI1 or similar firearm, then wrapped around the trigger guard and looped onto the trigger. With the correct length and tension, the travel of the bolt will pull the trigger and continue firing until there is a malfunction or you run out of ammo. Well now there is a new DIY method for an AR-15. The coat hanger machine gun.

    Ben Winslett is an FFL/07 and he manufactured a drop in auto sear (DIAS) out of a coat hanger. For those not familiar with a DIAS, it is a device that drops into an AR lower and acts as a secondary sear engagement. The DIAS is tripped by the movement of the BCG.

    The coat hanger machine gun DIAS is rather simple to make. Coat hanger, a pair of pliers, and wire snips is all you need to make a machine gun. A real machine gun. Not a bump stock machine gun.


    Yes, he registered the coat hanger as a post sample machine gun.

    I spoke with Ben about how he came up with the coat hanger machine gun. It was actually the Swift link that inspired him. When he saw how the Swift link worked he started looking around the house for materials to make something similar.

    Unlike a DIAS, the Swift Link and coat hanger machine gun works by depressing the disconnector when the bolt closes, releasing the hammer. This results in full auto fire.

    Both the Swift link and coat hanger machine gun DIAS are considered machine guns. Regardless of what you think, that is how the ATF defines them so they are regulated as such.


    Unless you are an FFL/07 or you want ATF to come to your house and shoot your dog.

    Nicholas C

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

    Any questions please email him at [email protected]