Hobbyist builds working assault rifle using 3D printer

If only John Brunner were still alive.

It seems the day of the hobby terrorist has truly arrived.

You can guess what' in my pocket.

The title is not true

It is one thing to build body parts, quite another to build the works - barrel, bolt etc. that would survive the first firing.

Also the tolerances of body parts would be wider than the barrel.

Can't we just be impressed by the technology and ignore debates about the product?

The guy has used home technology to produce something capable of handling high stresses. This could be applied to internal combustion engines given a few material improvements. It's one step closer to having a replicator in your house to turn out any gadget minutes after asking for it.

How long before FRM (Fabrication Rights Management) becomes reality?

The Mass Effect universe is rife with "omni-tools" that cam make anything out of anything. But said tools have "FRM tech" installed and most of the tech is heavily licensed.

3D printers in the real world are going to need this tech apparently, to prevent mass replication of unregisterable firearms. Once again, truth becomes stranger than fiction. And then we'll have refuseniks with 'illegal' 3D printer mods to work around 'FRM' to produce licensed goods without a license.

Edit for the author:

"AR-15 class assault rifle"

The AR-15 is, by design, semiautomatic only. It is not an assault rifle. The introduction of a lightning link, auto sear, or any other technology to make it fully automatic or have a selectable fire mode (other than "safe" and "semiauto/fire") is completely non-standard.

"the style of gun the US military has called an M16"

The M16 shares the direct impingement system of the AR-15, and some of the aesthetic differences, but that's about where the similarities end. The M16 has additional parts that enable it to fire in either fully automatic or burst fire mode (depending upon the model) as well as the ability to still fire on semiautomatic (without the so-called M16 parts kit, a rifle that had the auto-sear/lightning-link/etc. would only fire on automatic).

"The lower receiver of a factory-produced AR-15 is usually made of metal, typically stamped aluminum."

Incorrect. Most AR-15 lower receivers are milled & machined from a solid piece of aluminum. Some are forged, although those are less desirable due to structural weaknesses.

Fun note: most people were thinking it would blow up since lately there have been attempts at making a polymer lower receiver (rather than aluminum or steel), but most of them end in abject failure. Some rather spectacularly.

Silly.

You can make an all metal Sten gun in a garage, with pretty basic tools. A lot simpler and more reliable than this semi plastic "theoretical exercise".

Back about 15-20 years ago, they were selling de-weaponized Stens for collectors with a chunk cut out of the receiver, and another company sold a tube that could be cut to match. "Sort of a build your own program" Some of people did this as contrary to popular belief it is VERY hard to get a full auto rifle in the US.

What stopped most people is the penalties. The feds have NO sense of humor, when it comes to automatic weapons, and doing this and getting caught meant that you could pretty much kiss legal ownership of anything more than an air rifle goodbye forever. That is after they let you out of Federal prison...............

BTAF regs

Under U.S. Federal law a firearm constructed at home with 80% of the work being done by the individual does not have to be registered with the BATF. In the case of the AR-15 series of rifles the lower receiver (the part with the serial number on it) is classified as the Firearm. Neither the Bolt nor the Bolt Carrier have a serial number. So yes this is a legal firearm. Also the reason the lower can be made of Aluminum or Plastic is that there is no stress on the lower. I own a plastic lower and like it very much.

David Williams

Do I have to trot out the example of David "Carbine" Williams, who designed and built guns....while in prison?

http://en.wikipedia.org/wiki/David_Marshall_Williams

Quite an interesting story, actually.

But, maybe we need to ban prisons, since guns can be built in there!

Dave

Wow, affordable rampage killing for everyone. That's what Americans need.

So many laws, so little time

Technologically this is interesting but building a lower receiver like this without all of the byzantine permits and oversight by various agencies in the US it already breaks so many laws its not funny.

Hmm

Firstly in the US, there is no Federal firearm registration or licensing system in place for firearms that aren't covered under the 1934 National Firearms Act which covers fully automatic weapons, short barreled rifles and destructive devices. Background check records are destroyed after 90 days.

Most states do not have a firearms register or licensing system in place and the background check is there to ensure that convicted felons or others with certain histories can not purchase a firearm from a dealer. this does not however occur on private face to face sales.

Note too that under federal law anyone who may legally own a firearm may also make one and the only requirement for a serial number is that one be present if the weapon is ever sold.

AR15 receivers are usually forged or machined from billet aluminum, not stamped parts like an L85.

.223 would be an issue with a plastic receiver as it generates over 50,000 psi and considerable heat in the receiver. The AR15 taps expanding gasses and vents them back into the receiver to cycle the action, pinging a lot of high speed and hot debris and gas into the receiver body. Numerous companies make .22 versions of the AR15 in plastic. Printing the part is simply an evolution of the R&D process prior to switching to Plastic injection molding.

A much simpler action would be to buy an 80% receiver blank and a drill press to make a part. Many folks over here do that already.