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'Ghost Gunner' lets people make untraceable, homemade guns

Defense Distributed's newest project is a PC-connected milling machine that aims to streamline the process of self-assembling AR-15 semi-automatic rifles.

Defense Distributed's Ghost Gunner mill can get an AR-15 lower receiver finalized in an hour. Defense Distributed

What is a "ghost gun?" It's any type of firearm that is self-assembled and untraceable. It's one of gun control advocates and lawmakers biggest fears.

A few years ago, putting together such guns took insider knowledge and expertise. But with the growth of 3D printing, making gun parts has become easier. Now, with the release of a low-cost home milling machine, anonymously making firearm parts is even simpler.

Cody Wilson, the self-described anarchist who debuted the first 3D printed handgun in 2013, announced the launch of his newest project on Wednesday called Ghost Gunner.

The Ghost Gunner mill comes in the form of a compact, black, steel box. Defense Distributed

Ghost Gunner is a computer-connected milling machine that aims to streamline the making of metal lower receivers for AR-15 semi-automatic rifles. While putting together AR-15 lower receivers at home is nothing new, Wilson's machine could speed up and modernize the process.

So, why the lower receiver? Under US firearms laws, it's the one piece of the gun that's legally considered a firearm and carries the gun's serial number. Therefore, an AR-15 with a handmade lower receiver is completely untraceable.

The AR-15 is thought of as one of the most deadly guns in the US. Several mass shootings over the past couple of years involved an AR-15, from Aurora to Newton to Santa Monica.

To name his milling machine, Wilson borrowed the term "ghost gun" from gun control advocates. In fact, a large part of his project is to thumb his nose at lawmakers trying to outlaw the making of untraceable guns at home.

California state Sen. Kevin de Leon has been working to pass a law that would require self-made guns to contain permanent pieces of metal and be registered with the Department of Justice through a serial number and gun owner background check.

"Technological advancements require that we update our laws to meet new and growing public safety concerns to make sure dangerous individuals cannot manipulate technologies at the expense of public safety," de Leon said in August as his bill headed to the governor's desk.

Wilson, and his organization Defense Distributed, took de Leon's bill proposal as a call to arms.

"It just seemed to be such an affront and also a challenge," Wilson told CNET. "We used his creation and his words to trademark the project...The ball is in his court."

California Gov. Jerry Brown vetoed de Leon's bill on Tuesday (PDF) saying, "I appreciated the author's concerns about gun violence, but I can't see how adding a serial number to a homemade gun would significantly advance public safety."

Defense Distributed built Ghost Gunner from the ground up using open-source hardware. The compact cube-shaped mill is constructed with a rigid steel frame and its drill bit can ready a lower receiver to be fit into other AR-15 components in an hour.

The Ghost Gunner costs around $1,500. Wilson said the machine can reliably drill one lower receiver per hour at the production output of a machine 10 times its cost.

When asked whether he's nervous about the authorities cracking down on him, Wilson said he's tried to cover his bases.

"It's going to be news to me with whatever they come up with," Wilson said. "We tried to satisfy every letter of every law."

Correction, October 2 at 1:37 p.m. PT: An earlier version of this story incorrectly stated that an AR-15 was used at the Columbine mass shooting, rather it was another type of assault weapon. The story was also updated to clarify that "several" mass shootings in the US have involved AR-15s.