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Open Source United States Hardware Your Rights Online

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.
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Wiki Weapon Project Test-Fires a (Partly) 3D-Printed Rifle

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  • by eldavojohn ( 898314 ) * <eldavojohn@noSpAM.gmail.com> on Tuesday December 04, 2012 @01:02PM (#42180709) Journal

    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 someone who's taken gun safety, I'm shocked he put himself at risk to test this. Making a shooting bench is fairly trivial. Automating a trigger pulling mechanism is a little more difficult but would require very basic knowledge. I'm surprised someone with access to a 3D printer would be stupid enough to pull a plastic lower receiver up to his face, put his hand on it and pull the trigger until it failed. In gun safety they show you what even an obstructed barrel can result in when firing a gun. That action mechanism would basically become shrapnel for your right hand, left forearm and face.

    If these guys want to be taken seriously, they probably should 3D print something that will prevent them from winning a Darwin award.

    • by vux984 ( 928602 ) on Tuesday December 04, 2012 @01:08PM (#42180797)

      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: (Score:2, Insightful)

        by Dr_Barnowl ( 709838 )

        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?

        • by Afty0r ( 263037 )

          The hood is part of the structural strength of the vehicle.

          This may be true of some automobiles, but it's certainly not true of them all - many auto hoods now are the equivalent of tin-foil with more thickness of paint on them than metal in them... On my car (Honda S2000) you can make a significant shallow depression in the hood, depressing it only with the strength in your smallest finger...

        • by need4mospd ( 1146215 ) on Tuesday December 04, 2012 @01:50PM (#42181355)
          The only purpose of a hood is to keep stuff from getting in the engine bay and improve aerodynamics. If you think it adds structural integrity to the vehicle, I suggest you spend a little more time under the hood. Most hoods are attached at two points by weak hinges, real structural there. Not to mention, a common hood material is fiberglass which breaks up into shards fairly easy.
        • The hood is part of the structural strength of the vehicle.

          Citation required.

          I occasionally see vehicles with no hood whatsoever (or having an obviously fiberglass part, pinned down). I have yet to see any of them surrounded by angry tin stars, with the owner on the ground, trussed up like a chicken.

        • by tgd ( 2822 )

          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?

          That's not just wrong, its ridiculously wrong. The hood isn't remotely structural, in any form, in any vehicle. And no plastic shard is going to come from the hood and through the windshield and impale you. Ever.

        • by sootman ( 158191 )

          > The hood is part of the structural strength of the vehicle.

          Nearly none. It's held on the back with two small hinges and the front with a clip. It lends a bit of torsional rigidity but not much. Almost not enough to measure. Any car can be driven normally for great distances with no hood. The biggest downfalls are aerodynamics and getting water, dirt, and debris into the engine area.

          Also, plastic weak enough to shatter would not be strong enough to go through a laminated windshield -- it would just brea

      • Maybe you didn't hear - he took a gun safety class? He's totally an expert. Seriously - that's like someone on slashdot claiming they know what the article says because they read the summary. Oh, wait . . . carry on!
    • by Anonymous Coward on Tuesday December 04, 2012 @01:11PM (#42180831)

      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.

      • Is is just the stripped lower that is plastic, or is it the whole thing including the buffer tube?

        Remember that tube that the stock attaches to isn't just for that, it contains the recoil spring and buffer. The bolt carrier flies back against the buffer, in to that tube, and is then pushed back in to position by the spring. If it broke, you could get a face/arm full of spring and so on.

    • by swb ( 14022 ) on Tuesday December 04, 2012 @01:12PM (#42180843)

      Well, there's some risk, but it's pretty minimal. The upper receiver is likely metal, and the upper receiver holds the bolt and the barrel and chamber.

      It's hard to see what kind of problem you would have if the lower failed -- feed problem with a dropped magazine? Broken trigger guard, or just some larger mechanical failure if the lower itself cracked or split?

      None of these would result in a gun blowing up in your face as the cartridge is fired in the chamber which is an integral part of the barrel and connected mechanically to the upper receiver.

      It seems like a good machinist's face shield and a pair of gloves would be more than adequate protection for the risks involved.

      • by vlm ( 69642 )

        It's hard to see what kind of problem you would have if the lower failed

        Worst case scenario is some improbable failure of the sear leading to full auto operation while being filmed. Whoops. Then the jackboots nuke everyone involved from orbit, just to be sure.

      • by Anonymous Coward on Tuesday December 04, 2012 @01:50PM (#42181361)

        Well...
        As a person who actually builds ARs as a hobby let me follow up. The lower receiver is also where the buffer tube is attached. The buffer and buffer spring are absorbing the blow back of the bolt carrier group and is responsible for returning it to battery position. The point at which the buffer tube meets the lower receiver is a potential point of failure since the receiver is not aluminum. This also happens to be right about where your face is. If it breaks loose chances are the rifle will simply fail to cycle at all. Although if it breaks loose and you fire a second round you may end up with a BCG slamming into a broken buffer tube and having part of it lodged into the side of your face. Even if the potential for failure is small it does exist. Maybe it is just me but until you work out the kinks placing your face next to it is in fact extremely unsafe, face shield or not. One solution to this point of failure is to embed a threaded aluminum collar into the printed piece so the buffer tube had solid threads to anchor to.

    • by RobertNotBob ( 597987 ) on Tuesday December 04, 2012 @01:13PM (#42180845)
      Yeah, But...

      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.

      • To be honest I think they should be looking at different designs entirely to compensate for the poor quality materials, maybe even completely new designs.

      • by eyegor ( 148503 )

        There's a fair amount of stress where the buffer tube screws into the lower. Both from torque forces caused by the user pulling the gun in tight to their body while they shoot and stress caused as the buffer spring compresses when the gun shoots. The stress is nothing like what's seen on the upper, but obviously you don't want the gun breaking just because you've pulled in too hard while shooting.

      • by asylumx ( 881307 )
        If the high-stress areas are all in the upper receiver, then why did this lower receiver fail after 6 shots?
        • The portion of the recoil energy that the plastic absorbed caused it to crack. The job of the lower receiver is to hold all of the other pieces in proper alignment so they can connect properly to each other. Once the plastic failed, the other pieces fell apart.

          It took 6 impacts before the material failed- Just like a walnut that you hit with a hammer to get at the food; the first hit might be absorbed, but even if you're not swinging brittle shell material will develop cracks and eventually the shell will

    • by CasualFriday ( 1804992 ) on Tuesday December 04, 2012 @01:23PM (#42180993) Homepage

      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]

      • That's OK. Their sister organization the DEA (Drug Enforcement Administration) thinks Marijuana is a Schedule I drug(drugs you can't have anywhere, anytime), right up there with heroin , while the purified form of the active substance in Marijuana, THC (marinol [wikipedia.org]) is a Schedule III drug (drugs with much less of an addictive or medical issue, you can call prescriptions in by phone or fax, get refills of them).

        Dumb and Dumber!

      • by spitzak ( 4019 )

        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.

        Why is this? It seems like the serial number should be attached to some more important part of the gun, like the barrel? Especially since the barrel leaves rifling marks that are used to identify weapons. I would also suspect the barrel is going to be the last part to be 3D printed (not because of materials but because of the need to make it have a very straight hole and the ease of doing th

        • Re: (Score:3, Informative)

          by GigsVT ( 208848 )

          On some guns the upper section is considered the firearm. It depends on the gun. On the AR-15 it's likely the lower because the lower houses the fire control group (trigger/sear/hammer), which defines important traits such as whether the gun is full auto or not.

          The plus side to this is that you can often take a fully automatic lower receiver and use it with different uppers to effectively create different kinds of fully auto guns without needing to get separate tax stamps and avoiding the 1986 prohibition

    • I have never taken a gun safety class but this was the first thing that came to mind for me as well.

    • If these guys want to be taken seriously

      Seems more like they want attention / drama, which they're getting (from people who operate from fear, mostly). A good 3D printer is more expensive than a Smithy combo mill and the mill can actually make a full working gun. Do the attack tree analysis...

      If I was going to spend time making a gun for fun, it would be Jamie's 'pop gun' that shoots soda cans with compressed air from a fire extinguisher tank. That one 'killed' Buster and most people who can change the

    • by Nimey ( 114278 )

      I'm surprised someone with access to a 3D printer would be stupid enough to pull a plastic lower receiver up to his face, put his hand on it and pull the trigger until it failed.

      There's a reason D&D has separate stats for Intelligence and Wisdom, y'know.

    • As a kid we used to take a board with a hole drilled into it, put a rifle round in it and smack it with a hammer to set it off. Got good enough that we were actually hitting targets at 20 yards with it. No one was killed surprisingly. Where you have to worry about with bullets is A. being in front of it when it goes off... and B. having the gas trapped due to a poorly made bullet or a barrel obstruction. There's not really a way for what he made to fail in such a way that the gun would blow up. I'd be sure

    • On and AR-15/M-16/M4 platform the Lower reciever simply holds the trigger mechanism thats it. There is no safety issue. IF the trigger mechanism malfunctions then the gun just wont fire thats all. Its the upper reciever that you have to worry about on these platforms.
      • On and AR-15/M-16/M4 platform the Lower reciever(sic) simply holds the trigger mechanism thats it. There is no safety issue. IF the trigger mechanism malfunctions then the gun just wont fire thats all. Its the upper reciever that you have to worry about on these platforms.

        That's not completely true. The buffer tube also screws into the lower receiver. A failure of this while cycling could be bad.

    • Plastic lowers are really nothing new, you can get them dirt cheap. The only thing new here is that it's being made with a 3d printer rather than manufactured and sold. The only reason that's even interesting is that the lower is the part of the gun that's regulated so potentially anyone could create their own lower and order all the other parts.

      I agree their test method was foolish; but if not for guys like this we wouldn't get to enjoy the darwin awards each year as you pointed out!
    • 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.

      Actually, that's exactly what it is.
      The lower reciever is the "firearm" as far as BATF are concerned. The rest is just unregulated parts.
      So, if you want a gun, you have 3 (legal) choices
      Run down to Dick's Sporting Goods, hand over your Visa, and (after satisfying all the regulatory burdens), walk out with your gun.
      Wait for a gun show, find a random guy, swap cash and gun on the spot. More privacy, less convenience, no warranty.

    • If these guys want to be taken seriously, they probably should build an AK with a shovel and a vodka bottle :D
      http://www.northeastshooters.com/vbulletin/threads/179192-DIY-Shovel-AK-photo-tsunami-warning [northeastshooters.com]

  • I wonder what having techie types with superior firepower as the societal norm will do to the prevalent stereotype.

    • by Thiez ( 1281866 )

      Seems to me the military has superior firepower. And the techies aren't allowed to go around shooting people (just like the non-techies), so it doesn't even make a difference even if you ignore the military.

      It's likely that most techies could already have superior firepower today even without this technology, as they tend to have above-average income and having more Benjamins presumably buys you bigger guns.

      • In a civilian clash with the military, the military loses. At least half the military will defect to protect the citizenry, possibly more. With defective supergovernmental structures such as republics (i.e. the US), each state has its own military (in the US this is the "national guard"), which will likely defend its state from invasion by the central government's military with extreme prejudice. The citizenry, if sufficiently equipped, vastly outnumbers the military--in the US about half a million troop

    • If this is anything new for you... you might not have been paying enough attention.

      My IT industry friends are the most well armed guys I know.

    • I wonder what having techie types with superior firepower as the societal norm will do to the prevalent stereotype.

      Instead of a bunch of smelly, hairy, alcohol fueled crazies running around with guns, you will have a bunch of smell, hairy, meth-addict level Mountain Dew infused crazies (with yellow / orange greasy fingers) running around with guns.

      I, for one, welcome our new Mountain Dew swilling overlords.

  • by Nidi62 ( 1525137 ) on Tuesday December 04, 2012 @01:08PM (#42180785)
    Well, hell, if this qualfies as a plastic gun, then so is my Sig SP2022, and it survives a lot more than 6 rounds. A plastic lower is just a frame; just like my Sig, or Glocks, or numerous other firearms, the actual firing mechanisms(trigger assembly for lower; barrel, firing pin, chamber, and numerous other parts for the upper) are still made of metal.
    • Re:"Plastic Gun" (Score:5, Insightful)

      by ColdWetDog ( 752185 ) on Tuesday December 04, 2012 @01:25PM (#42181023) Homepage

      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.

      • It isn't a plastic gun any more than any other gun that has a plastic receiver is. The barrel, chamber, bolt, firing pin, hammer, etc, etc, etc are all still metal. This "OMG WE CAN PRINT A GUN!!!!11one" stuff is stupid.

        Yes, you can make the receiver, the low stress part, out of plastic. Big deal, this has happened for a long time. The barrel and chamber are the parts that face stress. Try that and see how it goes... But fire it remotely if you value your face n' fingers.

  • The recievers on Glock handguns are plastic, just to point out. Obviously, its possible to make plastic guns, just not by replacing plastic with metal

    Barrels, springs and working parts are the only thing that needs to be made out of metal.

    also 5.7x28 is a terrible calibre. Its pistol ammo, that at best has the knockdown and kick of 9mm, and at worst is an expensive non-standard cartridge. Its far overhyped, and far overrated.
    • also 5.7x28 is a terrible calibre. Its pistol ammo

      Strictly speaking, it's PDW ammo, not pistol ammo. Or in other words: coincidentally, there's a pistol for it - one, as far as I know. Does that really make it "pistol ammo"?

      • by GigsVT ( 208848 )

        According to the ATF it does. This has consequences in the types of bullets that can be used. If something can be chambered in a pistol, generally you can't easily get armor piercing ammo for it for civilian use.

  • Is it too early to set up a kickstarter to pay for the finger reattachment that one of these plucky alpha testers is going to earn himself?

    "So, um, guys, I'm working on a project that will involve briefly generating an overpressure of up to 50 thousand PSI accompanied by a release of heat, probably not more than a dozen cycles within a one minute period. It's handheld. What 3d-printable thermoplastic would be best?"

  • by Anonymous Coward

    Object and Stratasys have completed their merger yesterday, so we'll see about that "libertarian mindset"...

  • by Trepidity ( 597 ) <delirium-slashdot@@@hackish...org> on Tuesday December 04, 2012 @01:23PM (#42181003)

    Because of the weapon's design, the receiver on an AR-15 is a notoriously easy part to produce, and has been possible to produce on low-end CNC mills for years. It's not in any way the most difficult part of the weapon to produce; it's just the outer housing within which the actual functional parts are located. Sort of like printing a computer case but not printing what goes inside the case.

    • by mr1911 ( 1942298 )

      Because of the weapon's design, the receiver on an AR-15 is a notoriously easy part to produce, and has been possible to produce on low-end CNC mills for years.

      And before that it was designed to be stamped -- very low cost for very high production rates.

  • Why that round? It's not a rifle round (making the "printable rifle" really a "printable carbine") and it's not even a standard AR rifle round (which is traditionally 5.56x45, but the design is flexible..).

    I would think for initial builds you'd want to at least target the baseline round for an AR, 5.56x45, or if they really want to work out the bugs, 7.62x51 NATO, which is a much more powerful cartridge and thus making the design guaranteed to be backwards compatible (from a strength perspective) with 5.56

    • by tnk1 ( 899206 )

      I think they are more concerned with proving the thing will fire than having a rugged design at this point. The goal is to fire something and have it less likely to have it blow up in your face (literally). For that reason, they probably don't want to start with 5.56mm and particularly not 7.62mm rifle rounds.

      Of course, again, as has been pointed out, the lower receiver is probably not going to be challenged very much by what you fire.

  • While the lower receiver doesn't see the kind of stresses that are present in the upper receiver and bolt carrier, the lower receiver failed exactly where it sees the most real stress. As the bolt carrier moves backwards during the ejection phase of the cycle, it compresses the buffer spring and that stress plus the stress caused by the stock attachment was more than the lower could handle.

    Personally, whenever I test fire a gun, I put it in an appropriate test jig and make sure I'm clear from any likely fai

    • by vlm ( 69642 )

      I've seen prices on 3d printing for metal and the prices to render a standard lower receiver would have greatly exceeded the cost of buying a conventionally manufactured one.

      The "fun" with 3-d printing seems to be mash up. Next up the "hello kitty" themed AR-15 lower. Yes I've seen pink 1022s, but I'm talking about full on copyright violation ar15 lowers. Or a lower with a goatse themed trigger guard.

  • Yeah, you can't make the other parts out of plastic because of the pressure from the round, but you could reduce the pressure and projectile speed making it a lot less lethal but still usable for targets and defense. There really isn't much between paintball/airsoft and lethal firearms. I wonder if there would be a market for people wanting something like that.

    • Even the pressure necessary for match grade air rifles would be too much for plastics. That is, if you want any real accuracy.
      • by GigsVT ( 208848 )

        They've made barrels that are a sleeve of fairly thin metal wrapped in fiberglass before. I think it was mostly a gimmick and never caught on though. That'd probably be the minimum amount of metal you could get away with in theory, a sleeve for the chamber and rifling, wrapped up with reinforcement.

  • Area man uses CNC machine and metalsmithing lathe to build a gun! Complete with Barrel, upper and lower receiver!
  • by sl4shd0rk ( 755837 ) on Tuesday December 04, 2012 @02:20PM (#42181819)

    A busted beer bottle can be a weapon, or just a busted bottle. It all depends on the responsibility of the person holding it.

    It makes no sense to me to panic about printing a firearm, or pieces of it, when I know any dumbass could just as likely run me over with his/her car while texting on their phone. Point is, address the problem of bad decision making instead. Running around making prohibitions just causes people to be more sneaky about obtaining said item anyway.

  • This is a PR stunt. It's not like guns are expensive or hard to get in the US. It's not good engineering, either. If you're going to design a plastic gun, design a plastic gun, accepting that it's weaker than metal but you can form more complex parts. Maybe the whole trigger assembly can be made in one piece, with flexible parts. Replacing individual parts from a metal gun with inferior plastic parts is a PR stunt.

    3D printed plastic parts tend to be weaker than injection-moulded plastic parts. The bon

  • Let's revisit that:

    "...with the purpose of creating an open-source gun [...] that can be downloaded from the internet and printed out."

    Right, because what's really holding back modern society is this frustrating lack of weapons availability. I can hardly wait for 3D nano printers so EVERYBODY can download their own Ebola virus from the internet and print it at home!

  • by Paracelcus ( 151056 ) on Tuesday December 04, 2012 @05:38PM (#42184813) Journal

    Some poor bastard in a village blacksmith shop who can't read or write can produce AK47 clones day in, day out, that work!
    Unless somebody "prints" a REAL rifle (one that can fire thousands of rounds of a useful cartridge (7.62x51) without a major failure I call this just more kids indulging in mental masturbation, trying to entertain themselves.

  • by musth ( 901919 ) on Tuesday December 04, 2012 @10:53PM (#42187783)

    Fantastic way to invest time and passion. The world, especially the US, needs MORE GUNS.

    Idiots.

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