Defense Distributed Perfects Its 3D Printed AR Lower, Fires 600 Rounds

    February 27, 2013
    Zach Walton
    Comments are off for this post.

After successfully 3D printing a high capacity magazine, Defense Distributed got back to work on perfecting its 3D printed AR lower. The first attempt failed after firing six shots, but the group was obviously not going to give up.

In a recent blog post, the group said it had “printed AR lowers figured out.” It also shared the following image:

Defense Distributed 3D Printed AR Lower

As you can see, the AR lower looks pretty much the same as last time. The team presumably made some structural changes in the build, however, to make it stand up to the heat and pressure created by firing multiple rounds at once.

The new lower has exceeded expectations by staying intact and operational even after firing 600 rounds from an AR-15. Here’s the video:

The team hasn’t shared what it’s going to work on next, but a question posed on their blog indicates that the team may be working on making 3D printed magazines for more gun types.

  • Red_Blue

    To understand this development, you need to understand US gun laws. While there is no conceivable technology known to make parts strong enough to handle the chamber pressures of a firearm (basically the barrel and the breech closing mechanism, in the AR that is the bolt and the bolt carrier) from non-metallic printable materials, these parts are unregulated. Only the lower receiver (which was made in this project) is regulated, mostly because it holds the trigger mechanism which determines the type of action (fully automatic “legal machine gun” or a self loading or semi-automatic). So if you can make the lower receiver yourself, you can buy the other unregulated parts outside of legal gun control.

    I suspect this will lead to attempts to regulate more firearm parts. In other parts of the world, more essential parts are regulated, numbered, tracked and licensed. Typically the parts you cannot get past government control are the barrel and the breech closing mechanism, the so called “pressure bearing parts”. The anti-gun nuts would love to close that “loophole” in US gun legistlation, to be able to regulate more essential firearm parts, because regulating just the receivers or frames is no longer effective.

    There have been a lot of so called “free gun” or “rogue gun” projects, which aim in making very easy firearm building instructions, that will allow building of effective self defense firearms with typical home shop tools and home depot materials. The 3D printer is basically a cheaper version of a 3D CNC mill, which are becoming more affordable each year. With a small CNC you can easily make the breech closing mechanism, which leaves only the barrel to be acquired from other sources.

    Earlier free gun projects and blueprints tended to use much simpler technologies, such as laminated metals, folded and riveted sheets, sawing instead of cutting operations, etc. With these plans you can make effective long range weapons with access to barrels and effective short range weapons (shotguns, smoothbore = unrifled guns) with access to standard steel tubing.

    However, probably the easiest method of controlling effective firearms availability is the control of ammunition. It’s much more difficult (and hazardous) to make smokeless gun powder and especially primers for modern cartridges than the firearms themselves. Strictly controlling complete ammunition and primers would be enough to bring the level of technology attainable with easily home manufactured weapons back about 150 years to black powder and primerless ignition.

  • Fred

    The way that this process is described is that anyone can duplicate a working firearm by only scanning the complete item.

    This is not true. Each part of the firearm would have to be scanned, 3D printed and then assembled. In addition each part would have to be made from a material similar to the original part. Not as easy as you think.