3D Printed AR-15 Lower Receiver

Everyone is jumping on this bandwagon now because of the implication:

Check out Gunsmithing with a 3D printer Part1 and Part2 for the details.

I really hate the phrase “world’s first ______” which a lot of websites are using to describe this experiment.  3D printing is over a decade old, and downloading a firearm related 3D CAD file and feeding it into one of these printers has been done a million times.  The only reason this is making the rounds right now is because of the Aurora, CO massacre. 

“OMG you can PRINT A GUN!” is what people are saying.  So much for gun control if you can just print one, right? *facepalm*Sure the lower is considered the “firearm” as far as the ATF is concerned because it is the serialized part.  The AR-15 lower is such a simple receiver that people have even made them out of cutting boards.  I’ll be impressed when an entire functional firearm is printed, barrel, components, and all.  


Hat tip: The 20+ of you that emailed me.


21 responses to “3D Printed AR-15 Lower Receiver”

  1. TomThumb Avatar

    at least its not full auto… on the other hand there’s nothing illegal about “manufacturing” a AR15 from unfinished receiver blank with no markings what so ever… so this person manufactured 100% of his…

    “nothing illegal” see http://www.atf.gov/firearms/faq/firearms-technology.html
    see item 4: “Is it legal to assemble a firearm from commercially available parts kits that can be purchased via internet or shotgun news?”

  2. Well, yes, things like this do show how pointless and ineffective “gun control” is. If idiot politicians (but I repeat myself) ever wanted to ban AR-15s, even a caveman like me could purchase one of those whizbang 3D printers and crank out a couple… for my own use, of course.

    Once methods of production get distributed to the people, attempts at controlling them are simply entertainment, not good politics. ‘Course, I would rather our politicians focused more on “entertaining” us than trying to accomplish “good” politics.

  3. bikeman Avatar

    I’m with you in the printing of an entire firearm, however, More impressive would be actually putting rounds downrange through an entire printed firearm, and not having it grenade after a magazine. *apparently someone did this with a .22 and it worked for 200 rounds.

    Speaking of which, how come we aren’t seeing a ton of 3D printed magazines? MagPul could be out of business pretty quick if someone came up with a solid, reliable design…

    1. Because the plastics used in most 3D printers is pretty weak to start with, plus the “extrusion” method used to deposit the material often leads to weak areas where layers fail to bind or bind poorly. As I noted below, HB’s receiver cracked in two places *just putting the pins in*. (It’s ABS plastic- he fixed the cracks with a solvent glue.)

      Even in multimillion-dollar industrial printers, the plastics are fairly weak, even for a plastic. The printed part is typically just used for fitment and placement type testing- it’s cheaper to print a part to see if it fits, than it is to machine a metal part.


      1. Steve P. Avatar

        And the material is really expensive, at least expensive enough to make printing mags cost prohibitive when you can just buy reliable ones.

        1. but you could print a 50,000 round magazine!

  4. While you’re probably right about the story getting traction thanks to Aurora, it might well actually BE the first time somebody has actually printed, assembled and fired an AR lower.

    It didn’t look like anyone at AR15.com came up with a prior example, and even in an industrial setting (as in, a large manufacturer with in-house prototyping) chances are anything printed was just for fitting and checking, and was never fired.

    If nothing else, I’d lay a few bucks on it being the first time somebody’s done it with a privately owned 3D printer, anyway.

    But yeah, the level of inaccuracy in all the reporting is amazing. And I’m not just talking the opinions and politics- even with HB carefully detailing the entire thing in his blog (note that the receiver cracked in two places just while he was assembling it!) writers were getting virtually everything wrong, other than that it was a gun, and parts of it were 3D printed.


  5. @Bikeman: that link is about the same receiver that’s shown above. He tested it as a .22 pistol first, then built it up into a .223 rifle. He’s blaming the upper for why it wasn’t working well, as he moved it to a different lower, and it still had the same problems.

    1. bikeman Avatar

      Didn’t put 1 and 1 together, no idea why. Need caffeine….

  6. Bob Barker Avatar
    Bob Barker

    Just wait until they discover you can make functional unserialized AKs with nothing more than a bench vise.

  7. Having worked in 3D printing since 2006 for 3d Systems and various other organizations, I can tell you this: 3D Printing is for prototyping parts. In fact the industry is Rapid Prototyping. On industrial grade machines in SLA like the Viper, Viper Pro and 6000 you can easily replicate an object up to a thousandth error in whatever cad file you are building. The only limits to what you can do with that part lay with the resins used. There are some very high heat, high impact extreme resins that could probably sustain a lower for quite some time, if not indefinitely. However, these resins are expensive and require alot of extra work to get right in the build process. In other words…You would have to be a service facility to do it. As for these DIY layering printers….You are limited by the resins. The extreme resins I spoke of only work in SLA (90+mw Laser and up). If someone invented a good high impact / heat resin for one of those DIY printers, then printing lowers would be more feasible. As for the entire gun…..The only way I would try that is on an EOS machine which can 3D print metals…even then…iffy.

  8. SidViscous Avatar

    Legally I can’t see how this is any different than downloading a CAD file and machining a lower on a 5 axis mill.

    Making a firearm is making a firearm, whether it’s with metal, plastic or carved from soap.

    granted 3D printer ones are a bit more accessible than 5 axis mill ones, but I still don’t see the difference.

    1. ENDO-Mike Avatar

      It’s not any different, but people hear “print” “plastic” “cheap” and they shit a brick.

      1. And don’t forget, it’s plastic so metal detectors won’t pick them up….OOOOHHHH Scary

  9. isnt this how glock has being doing it for years?

  10. I really don’t see these printed AR 15 lower receivers being very effective. Their not made out of high grade polymer and they don’t have any reinforcement around the buffer tube area. After several rounds of 5.56, I doubt these will hold up. Maybe for a .22.

    Anyways you can make an aluminum AR 15 lower receiver using a CNC machine or drill press (if you have the patience) or buying an 80% lower and drilling out the firing cavity. The government says it’s completely legal to build your own firearms without SN numbers.

  11. gaimesniper Avatar

    big deal, for less than $4000.00, you can purchase a surplus cnc vmc and produce ar-10 or 15 lowers and produce over six an hour. Do not need a five axis, older, simple three axis works beautifully. Now that Obama has been elected, there are many good deals available. They are practically giving these machines away.

  12. It’s not as easy as people would have you believe. AK 47 on the other hand. Guys have made them out of a shovel. Lol. Look it up.

    If you believe the liberal media, high capacity “clips” and assault weapons are legally purchased and used in drive bys and mass murders all around the country.

    Yeah right…I’m sure they all went through the CA background check and went out on a shooting spree after. How fucking stupid.

    Inanimate objects don’t kill people. People kill people. If we were to apply liberal ideals to all dangerous objects…then We should ban forks, spoons, cars, belts, rope, chairs, and anything else that can be used for evil purposes.

  13. Shit, I can kill you with a diaper!

  14. gaimesniper Avatar

    Why use plastic? a less than $4000.00 surplus vmc will do a fine job out of 7075 aluminum. check out some of the fine AR lowers being made on cheep $600.00 hand mills on u tube. I have personally examined some that easily exceeded standard military specs. Lets face it. In this age of modern machine tools, building a fire arm takes far less skill than the old blacksmith days, well within the skill level of a very average machinist. For an AK, even less skill is required. I saw a beautifully made AR receiver out of carbon fiber scraps that I will bet anyone I could put 10,000 rounds thru without fear of failure.

  15. Reverend William G Avatar
    Reverend William G

    Of course it’s legal to make any gun whatsoever. The 2nd amendment gives me that right. No LAW can override that right. Don’t care who says so.