Wiki Weapon Project Test-Fires a (Partly) 3D-Printed Rifle 289
MrSeb writes "In its continuing mission to build a 'Wiki Weapon,' Defense Distributed has 3D printed the lower receiver of an AR-15 and tested it to failure. The printed part only survives the firing of six shots, but for a first attempt that's quite impressive. And hey, it's a plastic gun. Slashdot first covered 3D-printed guns back in July. The Defense Distributed group sprung up soon after, with the purpose of creating an open-source gun — a Wiki Weapon — that can be downloaded from the internet and printed out. The Defense Distributed manifesto mainly quotes a bunch of historical figures who supported the right to bear arms. DefDist (its nickname) is seeking a gun manufacturing license from the ATF, but so far the feds haven't responded. Unperturbed, DefDist started down the road by renting an advanced 3D printing machine from Stratasys — but when the company found out what its machine was being used for, it was repossessed. DefDist has now obtained a 3D printer from Objet, which seemingly has a more libertarian mindset. The group then downloaded HaveBlue's original AR-15 lower receiver from Thingiverse, printed it out on the Objet printer using ABS-like Digital Material, screwed it into an AR-57 upper receiver, loaded up some FN 5.7x28mm ammo, and headed to the range. The DefDist team will now make various modifications to HaveBlue's design, such as making it more rugged and improving the trigger guard, and then upload the new design to Thingiverse." Sensible ammo choice; 5.7x28mm produces less recoil than the AR-15's conventional 5.56mm. I wonder how many of the upper's components, too, can one day be readily replaced with home-printable parts — for AR-15 style rifles, the upper assembly is where the gun's barrel lives, while the lower assembly (the part printed and tested here) is the legally controlled part of the firearm.
Re:Did He Really Just Pull That Up To His Face? (Score:5, Insightful)
In gun safety they show you what even an obstructed barrel can result in when firing a gun.
Yes, but I'm having a harder time imagining what a defect in the lower receiver would cause that would be equivalent to firing a bullet into an obstructed barrel.
That's the car equivalent of 3D printing a new hood and then saying man that's crazy risky -- just look at the damage that can happen when the brakes fail.
Re:Did He Really Just Pull That Up To His Face? (Score:5, Insightful)
Seriously? What's the worst that's going to happen from a lower receiver breaking? It doesn't even approach the situation, in terms of danger, caused by a squib.
As someone who's been shooting, dismantling and repairing firearms for over 20 years, I'm inclined to think maybe you should stick to things you learned in your little gun safety class and not speculate too far beyond that.
Re:Did He Really Just Pull That Up To His Face? (Score:4, Insightful)
All of the high-stress areas are also in the UPPER receiver. If the upper receiver, chamber, barrel, bolt-face, cam-lock, and main spring are all from "typically manufactured" steel and aluminum parts, then using this weapon is not any more dangerous than firing a mass-produced AR. - Just less reliable.
Re:Did He Really Just Pull That Up To His Face? (Score:2, Insightful)
The hood is part of the structural strength of the vehicle.
What if you printed a hood from plastic that shattered? And you had a crash, and sharp plastic shards penetrated the windscreen and impaled you, "Omen" style?
Re:Did He Really Just Pull That Up To His Face? (Score:5, Insightful)
And hey, it's a plastic gun.
No, it's not. It's not even close to that. It's a plastic lower receiver with the rest of the gun being not plastic.
As far as the ATF is concerned, an AR-15 lower receiver is a gun because it is the part of the gun that is serialized. Of course, your statement is true if you're arguing above the legal authority of the ATF, an organization that considers shoelaces to be machine guns. [everydaynodaysoff.com]
Re:"Plastic Gun" (Score:5, Insightful)
Except those plastics were specifically designed for this purpose (IIRC that's the whole deal with Glocks - 'cheap' simple plastic guns). Not the whatever thermoplastic ribbon you get in a 3 D printer.
Real question: How many different kinds of plastic are available for these things? One of the interesting things about plastics chemistry is that there are hundreds, if not thousands, of different types available with different properties. Picking the right plastic for the job is a very important thing.