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The original Liberator handgun was printed using an $8,000 piece of equipment the size of a refrigerator. But for most people, something like a “Lulzbot AO-101” is more affordable at around $1,750. Unfortunately, the original plans were not completely compatible with that kind of printer and needed a little tweaking. Which “Joe,” an engineer in Wisconsin, has done and successfully tested . . .

From Forbes:

Eight of Joe’s test-fires were performed using a single barrel before swapping it out for a new one on the ninth. After all those shots, the weapon’s main components remained intact–even the spiraled rifling inside of the barrel’s bore. “The only reason we stopped firing is because the sun went down,” he says.

Just how the Lulz Liberator survived those explosions isn’t exactly clear. Joe claims that the plastic he used, the generic Polylac PA-747 ABS fed into most consumer 3D printers, is actually stronger than the more expensive ABS plastic used in a Stratasys printer. In fact, before using a Lulzbot-printed barrel, he and Guslick tested one made on Guslick’s Stratasys printer. That barrel exploded on firing, though Joe blames the problem in part on its having been printed with a smaller chamber, the space at the back of the barrel into which the round is inserted.

Joe’s printed gun contains a few more pieces of metal hardware than the original Liberator. Rather than print plastic pins to hold the hammer in the body, for instance, he used hardware store screws. Like Defense Distributed’s gun, the Lulz Liberator also uses a metal nail for a firing pin, and includes a chunk of non-functional steel designed to make it detectable with a metal detector so that it complies with the Undetectable Firearms Act. The rifling that Joe added to the barrel is designed to skirt the National Firearms Act, which regulates improvised weapons and those with smooth-bored barrels.

So there it is. People claimed that the Liberator was a flash in the pan, something that was only capable of being printed by expensive machines, impossible for the average consumer to make. And, even if they could, they said the barrels would explode. It looks like every one of the fairy tales that gun control advocates have been telling themselves to make this seem like it isn’t the end of gun control as we know it have been crumbling, one after another.

Oh, and the best part is this comment under the Forbes article:

Why isn’t everyone screaming to ban this technology! This is exactly what’s wrong in this country, allowing anyone with the capability to make guns at home! Don’t think for a minute that the scum bag criminals aren’t going to jump on this like a dog on a bone. Stop this now before it’s too late!

I don’t even know where to start with that cry for the government to step in and regulate away the bad guys . . .

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  1. Must’ve changed more than the barrel during this video. Trigger starts out white, ends up black.

    • Correct, we started out with a Lulzbot printed trigger, had issues and substituted my Stratasys printed trigger, which held up for a bit but finally broke, so it was back to another Lulzbot printed trigger.

      You’ll notice by the decreasing light in the video that this took us several hours.

  2. Since the rifling is digitally reproduced, I suspect the rifling is exact in each printing. In other words, the marks on the bullet from one gun would be identical to those in another gun.
    Would be interesting to see if there is any difference in the bullets fired from different guns.

    • Considering that they only got 450 ft/sec on a .380 out of this thing, I don’t think the projectile gives an eff about the rifling in this case.

      But even if it did, the placement of plastic resin for this machine isn’t as precise as the word “digital” is suggesting in your mind. Variances are pretty “large” on that scale for this class of machine.

    • I doubt the rifiling even makes a mark, and if it did, because its plastic, it is probably changing after every shot, until the rifling is eroded away.

  3. Even if you made 3D printed guns illegal criminals would still make them. Heck if you banned guns and confiscated them all tomorrow criminals would have them made on CNC machines.

    To “stop” “home made” guns you would need to confiscate every 3D printer, CNC machine and lathe in the country. But that dog won’t hunt. The Genie is out of the bottle.

    • 3rd worlders make AK-47s over charcoal fires in Afghanistan. They are going to have to confiscate fire while they are at it.

  4. …those night shoots are telling – a bit ‘o flash ejecting from the rear of the gun. Would this present a danger to the handler?

    • Yes, if you don’t have the firing pin retainer ring installed, expect to be getting a face full of firing pin when you pull the trigger (even using a string, we didn’t stand directly behind the test fixture to avoid the firing pin rocketing out).

      And as Human Being notes, eyes and ears were in full usage.

    • If you video any semi auto at night, especially straight blow back guns, you will be shocked how much comes out around the ejection port.

  5. Correct me if im wrong, but according to the ATF, isnt it already perfectly legal to make your own gun at home (as long as you are able to own one and dont sell it)?

  6. TO: All
    RE: History Repeats Itself…Again

    The way the federal government is responding to the advent of the 3D printer reminds me of how the Roman Catholic church reacted to the invention of the Guttenberg printing press.

    They went ballistic because then ANYBODY COULD HAVE A BIBLE. Not just the Roman Catholic church.

    Now, with 3D printers, ANYONE CAN HAVE A FIREARM.


    P.S. The resulting Wars of the Reformation were ‘interesting’. But reason won out over monopolies.

    • Please substantiate. I take slander against the Catholic Church very seriously.

      And by substantiate, I mean show a verifiable source that proves your point.

      • I can’t verify the printing press stuff, but they persecuted the HECK out of anybody translating the bible into anything other than Latin. Tyndale, Wycliffe, et al.

      • From

        The Catholic Church quickly realized the potential of the printing press as a challenge to its influence. Censorship was introduced into the print shop in 1487, when Pope Innocent VIII required that Church authorities approve all books before publication. The Church had censored books for centuries, though it became much more difficult to do so after the invention of printing. Controlling a dozen painfully copied manuscripts of a forbidden text may have been a manageable task, but controlling the thousands of copies churning off the presses every year was quite another matter. One of these forbidden texts was the Bible printed in any other language than Latin.

        • While it may be true that the Church “cracked down” on copies, I have a feeling that it was because the translation to other languages is painstaking and requires a thorough knowledge of both languages involved. I think they wanted to ensure that misinformation was not making it out i.e. bad translations.

        • @Prairie Patriot

          Not so sure. Even today, the stigma of someone reading their own Bible within the Catholic church leads to heresy and/or insanity… because unlike a friar, monseigneur, priest, cardinal, bishop, or the Pope himself, the average Joe just can’t handle it.

  7. I may be wrong on this, but one possible cause of barrel breakdown/bursting could be a lack of “leade” or freebore immediately in front of the chamber. If the bullet is shoved too tightly into the rifling when the round is chambered, or the chamber is a too-tight fit around the mouth of the case, it can result in higher pressures when the round is fired. I may not have all of that described in a technically correct way, but i do know that bad things happen if the chamber is too tight around the end of the brass case where the bullet is held. It acts as a sort of “super-crimp” on the bullet.

    (Correction requested from DyspepticGunsmith or other authoritative sources.)

    • You are entirely correct – the KB barrel was printed on one of my Stratasys machines, and I had no .380 ammo to test fit with. I designed the chamber to SAAMI spec, but my printer makes holes slightly undersized. So we actually had to press the cartridge in place, likely causing a compressed load, resulting overpressure, and pieces of plastic going downrange.

      Now that I actually have a few pieces of .380 brass, I can try sizing my chambers to match.

  8. “Don’t think that scum bag criminals aren’t going to jump on this like a dog on a bone”

    So a “scum bag criminal” is going to buy a $1800 printer to print a single shot pistol when PLENTY of $200 guns that hold many rounds are easily obtainable on the street?

    The stupidity makes my head hurt…

    • Lol you forgot the part where they have to learn how to use the technology and troubleshoot software and mechanical bugs.

    • No, a scumbag criminal will steal a printer and all the supplies to make this work. That’s why they’re criminals.

      Because the technology is complicated criminals won’t attempt it? Then why do I keep hearing about cyber crime.

      I told this to more than one inmate when I worked at the prison. If you worked half as hard at a real job as you did at crime you’d have a clean record and no jail time.

    • As many folks have said, the idea that, before the advent of 3D printing someone couldn’t make their own gun is just ludicrous. Everyone has been able to do this all along, now we can make a crappier version on an $1800 3D printer. When new materials become more readily available, then we’ll have something.

      • Various types of “zip” guns can be made with $20 of pipe and parts from the local hardware store. This has been the case for over 100 years. Just my opinion, it’s not that these Liberators can be made at home that so upsets “them”. It’s the fact that they can be made almost totally metal free by unscruplous folks and therefore are allegedly undetectable. I’m waiting for printable ammo! Then I’ll invest in one of these printers. (LOL)

  9. And 3D printers will soon be able to print food!

    Domino’s should get an FFL. Then we can have a large pepperoni and an AR with extra ammo delivered within 30 minutes.

  10. Wouldn’t “comply with” rather than “skirt the NFA” be a less sensational way of explaining why the barrel is rifled? The Federal regulations say a non licensee can make a firearm (if otherwise legal to own a firearm) as long as you don’t build it with the intent to sell, that doesn’t mean you can’t sell it.
    It sounds like the original chamber was too tight not allowing the brass to expand freely therefore exerting more pressure on the plastic material. This is not an issue with steel barrels except for making extraction difficult but could be if the plastic is only marginally strong enough. The rifling being an exact copy in each barrel is an interesting issue. Because the nylon covered bullets didn’t retain rifling marks S&W was forced to discontinue the Nyclad line of ammo IIRC. Maybe the Feds won’t be so concerned with homemade guns all firing bullets with identical rifling marks?

    • I would much rather skirt laws than comply with them. But then my ancestors were smugglers, moonshiners, and had a habit of tarring and feathering tax collectors.

      • I bet you comply with a lot more laws than you “skirt” but whatever, it sounds cool anyway.

    • The chamber in the first barrel was too tight, but the material is elastic enough that the tight fit didn’t directly cause the KB. Instead, since we had to press the round into place, we believe the bullet came unseated and we had a compressed load (and overpressure) as a result.

      • Not trying to be argumentative, just trying to help figure this out. I have a lot of experience building custom guns.

        Bullet set back reduces the internal volume of the case and certainly can raise chamber pressure. Given that you had to push the round into an undersize chamber I fail to see how that would set the bullet back in the case. The cartridge case has a larger OD than the bullet so how could the chamber push the bullet back? Bullet set back is caused in a semi-auto during the feed cycle when the bullet hits the feed ramp and the case is not holding the bullet tight enough. Do you think the tight chamber increased the bullet pull, that is the energy required to get the bullet started out of the case, was enough to spike the pressure? That seems unlikely to me.

        • Well, I also had zero freebore/leade in my barrel, and that’s where the bullet setback likely occurred, I think (I was in a hurry to get to testing, and had no idea how the barrel would turn out, so I ran the rifled bore cross section all the way back to the end of the brass). Also, I’m not getting as much interlayer fusion on my prints as Joe did, so that weakness probably also contributed.

          As mentioned, though, now that I actually have a few .380 cartridges I can try and fit my prints appropriately. Hopefully I can determine if the KB was indeed from bullet setback, or just inherent structural weakness.

          I appreciate the insight, BTW – I’m still fairly new to the intricacies of chambering, so much of this is learning-as-I-go.

    • Didn’t Remington used to make a line of “Accelerator” ammo which used a plastic sabot on a smaller (.223) bullet in .30 caliber, to achieve very high varmit-shooting velocities in .30-06 rounds? Seems to me those would be as “untraceable” as a sabot slug from a shotgun.

  11. Definitely interesting. I love how everyone is freaking out. How about worrying about shaping future generations minds around the concepts of right and wrong (none of this “it’s all relative” BS). That will do more good for our future than any law can.

  12. That there is an insurance policy of the Second Amendment. That is the only thing that assures that any gun control efforts will blow up in their face.

  13. I love the pearl-clutching going on over at Forbes.

    For all those who would hyperventilate about this stuff. Cody was a law student and interested in the legal and PR ramifications of the issue. He’s less interested in perfecting the technology. Still, credit is due to Cody: He proved it possible, put it out there on the ‘net, then stood back to take the heat.

    Here you have two engineers decide to start putting their talents to work on Cody’s design, and what do we get? About what I expect. Rifling, and multiple shots per firearm. Oh, and a reduction in the barrier to entry.

    For all those pearl-clutching journalists out there, here’s a thought to sleep on:

    There’s nothing you can do to stop engineers from rapidly innovating this technology now. If I had the time, I’d be playing with this stuff too, but I don’t. Besides, I’m hardly the only engineer (or retired engineer) who likes to make and experiment with guns. There’s thousands of gun tech/hobby engineers in the US, doing everything from gunsmithing to metallurgy to programming CNC machines to crank out high quality guns in quantity. They’re in every sector of the gun market, from benchrest shooting, to making increasingly effective suppressors, to better ammunition and more accurate (or lethal) projectiles, better concealable handguns, you name it.

    So for those who have been losing sleep over the issue of 3D printing of guns: You might now want to start stocking up on Depends[tm]. Cody’s proof-of-concept has attracted the attention of the serious gun technology nerds, and now the advances will start in earnest.

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