Ghost Gunner Miniature CNC Machine Brings Homemade Gun Manufacturing to the Masses

Ghost Gunner Miniature CNC Machine Brings Gun Manufacturing to the Masses
Ghost Gunner Miniature CNC Machine
Defense Distributed
Defense Distributed

Teaxs – -( 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.

More than Guns

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.

Ease of Use

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.

DD Files

The .dd file format is itself open source and not constrained to the Ghost Gunner or Defense Distributed; any user can define any existing machine’s specific parameters via the machine parameters list. A single file can contain specific code and installation instructions for any number of machines. A user with both a Ghost Gunner and a Tormach P1100 could manufacture a particular .dd file on either machine and manufacture the same physible with zero additional user knowledge, as only the instructions required for a particular machine are revealed to the end user. The .dd file format is a CNC response to 3D printing’s universal .stl file format.

For those who have a favorite CAM program and don’t want to share your design via our new file format, Ghost Gunner will also accept TinyG code from any CAM program.


Ghost Gunner uses a compact, powdercoated A36 steel frame and thick stainless T-slot rail, with preloaded ball bearings for maximum rigidity. Linear motion is achieved with low-backlash direct-drive ballscrews mounted in-line with the cutting surface, thus preventing torsional gantry chatter while machining. Most of the machines in our price range use belted or all-thread motion components, which are susceptible to chatter due to elongation or thread gapping each time the force direction changes.

Ghost Gunner incorporates an electronic probe that automatically detects when the machine comes into contact with your part, allowing automatic part discovery and alignment. Ghost Gunner requires conductive parts if auto-discovery and alignment are used. Ghost Gunner is more than capable of manually machining nonconductive materials, but this requires manual calibration of a part to the machine – following a few simple instructions – as is required with existing CNC machines.


To contain aluminum chips, Ghost Gunner includes a chip collection tray and all moving components are fully enclosed. No messy lubrication is required, as the machine mills in a manner that contains the heat in the chip load. In addition, the machine is capable of manufacturing deep pockets due to its vertical gantry, which allows gravity to pull chips away from the cutting surface before they can build up and dull the end mill, as is the case on traditional CNC designs.


CNC mills with this level of automation retail for thousands of dollars, but Ghost Gunner gives you an affordable, automated package without sacrificing quality. After our initial pre-order campaign, Ghost Gunner will retail for under $1500.


  • Ghost Gunner
  • Machinable dimensions: 175 x 75 x 60mm (~6.75 x 2.95 x 2.35″)
  • Maximum part dimensions: 230 x 90 x 100mm (~9.05 x 3.50 x 3.90″)
  • Overall footprint: 330 x 280mm (~13 x 11″)
  • Weight: 20kg (~45 pounds)
  • Spindle Speed: 10,000+ RPM (Final Value TBD)
  • Requirements: Windows 7 or higher. Mac version TBD.

Open Source Hardware

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.

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I greatly respect all endeavors that promote free enterprise , especially when it comes to a terrorized society that has grown tired of being threatened by violent oppressors who think they can over-power an individual with little or no resistance. A loaded weapon in the hands of any individual with the intention of afflicting mortal wounds upon an unsuspecting assembly or simply relieving..a helpless victim of certain personal Property….with either circumstance their is one common denominator ….over-whelming intimidation and fear of death that is caused by the appearance of a firearm, whether it be a hand held pistol or a… Read more »


I have paid my deposit, how and when do I get my mill?I will come an pick it up, where are you located?

GhostGunner Owner

I’m just got and used my Ghost Gunner, so I’m offering an Ask Me Anything on Rededit:


My oh my Jack, why so critical of what people choose to have? If you want a $2,500 AR that’s your business, if I choose to build one for under $800, that’s my business. A cheap “Saturday night Special” will kill you just as dead as a $2,000 Kimber all fine tuned and everything. Besides, you’re underestimating the capabilities of people when you assume they don’t always know what they are doing. That’s the problem with elitist politicians that think they’re doing us a favor when they over regulate us to death, they know it all and the “great unwashed”… Read more »

Jeramia braaton

How much and how do I get one


“If somebody is making this (a legal product), into this (another legal product, also protected by the 2nd Amendment), my job is to stop them”. Who was that man in what looks like a police department evidence room? Could it be the Chief of Police from some small town or large city out to deprive their citizens of legal endeavors under the fear that they will pursue illegal activities?

Never underestimate the innovation of a free market.


The more that fool from CA talks, he reinforces his stupidity.


Great. More people can build more trash guns. Now the idiots who get conned into buying poorly built AR-15’s can get further conned into buying mini-mills to turn out even more poorly built guns.


Glad to see this. Both from a practical standpoint (harbor freight mini-mill does quick work on this already, but this will make it that much quicker), as well as an ideological standpoint.