Manufacture Your Own AR-15 at Home With Defense Distributed’s ‘Ghost Gunner’
Ghost Gunner is a non-profit open source hardware effort by Defense Distributed. Ghost Gunner builds on the open source community’s existing hard work, including the gshield 3 axis motion hardware, the grbl g-code parser and motion controller, and the legendary Arduino microcontroller. All GhostGunner schematics and design files will be published into the public domain. Defense Distributed decided to build our own machine from the ground up. We found existing CNC machines too expensive, too DIY, or too inaccurate to manufacture firearms for the casual user. By miniaturizing the build envelope to just large enough to mill common firearm receivers, we were able to improve rigidity, reduce material cost and simultaneously relax some design limits, allowing us to sell an inexpensive machine with more than enough accuracy to manufacture firearms.
Ghost Gunner has undergone several design revisions to reduce machine chatter, backlash, and jitter, all with the goal of keeping total design cost low. Rather than using plastic, wood, or even an aluminum frame, Ghost Gunner is constructed with maximally rigid plasma-cut A36 steel and 304 stainless steel. In addition, the machine part count is greatly reduced compared to a traditional CNC, which both increases rigidity and further decreases cost. The end result is a small, cheap, and simple machine that exceeds most consumer-priced CNC machine specifications.
What is Ghost Gunner
Ghost Gunner is a miniature CNC machine designed to automatically manufacture publicy created designs with nearly zero user interaction. No prior CNC knowledge or experience is required to manufacture from design files. Defense Distributed’s first design is the venerable AR-15 lower receiver. Ghost Gunner automatically finds and aligns your 80% lower receiver to the machine, with simple installation instructions, point and click software and all required tools. Just follow a few simple instructions to mount your 80% lower receiver, tighten a couple screws (with simple tools we provide), and on day one, Ghost Gunner can help you legally manufacture unserialized firearms in the comfort of your own home.
As shipped, Ghost Gunner can manufacture any mil-spec 80% AR-15 lower receiver that already has the rear take down well milled out. Lowers with non-mil-spec trigger guards that are otherwise mil-spec are also compatible. Defense Distributed recommends using the 7075 Ares Armor Raw 80% Lower AR-15 Billet, available for purchase here.
Ghost Gunner is capable of manufacturing more than just firearm receivers. With Defense Distributed’s open source Physibles Development SDK (pDev), designers can distribute files via our ‘.dd’ file format, which contains all installation and assembly instructions, any required jig files to hold the part in place (that users can print with a 3D printer), and all machine definitions and code to physically manufacture a particular design.
To a casual user, the .dd file is a one-stop solution to manufacturing any aluminum physible that the public can design to fit into the build envelope. Defense Distributed will be developing in and supporting this format, and we are happy to publish your own innovations and contributions.
If you can assemble a firearm or operate a 3D printer, you can use Ghost Gunner.
Ghost Gunner ships fully assembled and ready to build right out of the box. No assembly is necessary and no programming is required. After installing the included software, you’ll be ready to manufacture publicly available .dd designs. Defense Distributed is committed to releasing future firearm design files, from the AR-15 to the AR-10 to the 1911, and then continuing with our own designs.