Hasta La Ideas

The gun control debate may be over. In order to understand why, we need to look at the anatomy of the AR-15, the assault rifle that’s currently dominating the headlines.

One reason that the AR-15 is popular among gun enthusiasts is because it’s infinitely customizable. Owners can select from a variety of different barrels, stocks, upper receivers, scopes and sights; the Ballistic Advantage blog refers to the AR-15 as “LEGO kits for adults.” Those parts can be purchased from a variety of manufacturers with little difficulty.

If all of those parts can be swapped, then what makes an AR-15 an AR-15? Technically, it’s this:

That’s called the lower receiver. The lower receiver houses the grip, the trigger assembly, the safety, the magazine and the magazine release button. The lower receiver is the only part of the rifle with a serial number on it–because it’s the only part that the government regulates. If you want to manufacture, import or sell the lower receiver, you need a Federal Firearms License, or FFL.

To skirt this, a variety of companies manufacture what are called “80% lower receivers:”

These are cast and partially machined billets of aluminum or polymer that are, as the title implies, roughly 80% of what a finished lower receiver is; they lack the final machining to accommodate the moving parts that would make it work. There is no legal obligation to put serial numbers on these and they can be purchased for as little as $50. In the eyes of the law, this is not a firearm, just a chunk of metal. The images below are how the ATF defines them:

With a drill press, a milling machine and some patience, one could pocket out the space for the trigger, the fire control cavity and the holes for the pins, bringing the part to completion. This is legal, if you’re making it for yourself. According to the ATF, “Firearms may be lawfully made by persons who do not hold a manufacturer’s license under the GCA [Gun Control Act] provided they are not for sale or distribution and the maker is not prohibited from receiving or possessing firearms.”

Previously, someone would still need some mechanical aptitude and access to machine tools to complete a lower receiver. But now Defense Distributed, the “anti-monopolist digital publishing” company founded by Cody Wilson to promulgate the efficacy of DIY digitally-fabricated firearms, has largely removed that last barrier by creating the Ghost Gunner.

The Ghost Gunner (now in its second iteration) is a highly precise, $1,675 desktop-sized open-source CNC mill with a horizontal spindle. With this machine, virtually anyone can turn 80% lower receivers for AR-15s and M1911 pistols into finished, functioning parts.

In the first half of the video below, you’ll see just how easy this is to do. In the second half, you’ll see a 3D-printed-gun hobbyist who has managed to design and print a firearm with a lower receiver made from PLA plastic. Plastic was previously deemed not durable enough for firearms applications, but said hobbyist estimates he has fired roughly 5,000 rounds with his and it’s still ticking:

In the video below, Wilson explains what led him to create the Ghost Gunner, and the answer was not the typical pro-gun rhetoric that I expected:

Lastly, here’s Andy Greenberg from Wired, a man who admits he has no experience with tools, seeing if he can build his own AR-15:

It goes without saying that this makes our current gun legislation, and the debate we’re so evenly split on, kind of moot. We already don’t know the precise number of assault rifles currently in circulation in the U.S. And that refers to just the ones that have serial numbers and were legally purchased. Now that virtually anyone can build one without reporting it, tracking these guns, let alone regulating who can and cannot have them, seems virtually impossible.