3D Printing is not about to put Magpul out of business

Over the weekend I asked if any readers with a 3D printer could try printing the AR-15 magazine I linked to a couple of week ago. A few readers emailed me to say they would attempt to print the magazine. Donald of AE Innovations, was the first reader to respond with photos of a printer magazine is Donald. His attempt was less than successful.

Donald says …

  1. 3D printing at home is fiddly. It is also slow. Printing the magazine components in total took hours. They need some cleaning up afterwards, too. They do not come out looking as clean as in that fellow’s pictures.

  2. My print (I did only one attempt so far) I would consider a failure because when I printed the parts – using molten ABS – I neglected to account for the shrinkage of ABS (it shrinks about 2%) so it wound up being too short on the inside for the cartridges. It will probably feed only one round as is! The rounds do not physically fit inside the magazine body as it turned out (due to shrinkage, I think.)

  3. The designer leaves some key stuff out of the design, like the spring. I don’t know why he doesn’t share the spring design he made, but he doesn’t. I had to design a quick one myself to print out. The spring is a pretty critical component in a magazine, so “that looks about close enough” is not the best approach to making one. I doubt mine would reliably work (assuming my magazine printed properly next time.)

Looks like we will not be printing P-Mags anytime soon 😉

[ Many thanks to Donald and all the other readers who responded. ]

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • S O

    Can you use PC-ABS instead?
    It’s known for almost no shrinkage / warping.

  • calool

    thats really rough, it looks like it would jam your gun just by being near it! as for the spring i don’t think that the ones shown here and in the original photo would work, you could get a plastic spring that is good and reliable but they need a good bit of redesigning right now. i would love to see a proper gun company design and release the models for a printable mag.

  • Andrew Racek

    You can literally hear from that Magazine,

    • Mount

      I don’t think that “literally” means what you think it means.

  • David

    I would say ABS is probably not the best for prototyping due to the shrinkage. The only methods that I’ve seen where ABS is excellent is in vacuum formed parts where the ABS can cool on the mold under vacuum.

    The polymers used in commercial grade laser-sintering 3d printers like those made by Z-Corp or KUKA etc. are much more durable, stable, and can be strong enough for a proof of concept. Then again the most basic of these printers start in the mid five figures and go into the millions.

    Printing your own magazines could be fun, but I wouldn’t consider it cost effective and I certainly wouldn’t use them for anything other than testing a design or for light plinking.

  • Flounder

    LOL okay okay who really thought a spring could be made from plastic. Springs only work because the principles of the metal they are made from. If there is any plastic that exists that could make ANY kind of spring that is something I want to hear about!

    • K!P

      there are lots of springs made out of plastic, they might have different forms but it being done al the time.

      • Flounder

        Really!?!?!?! Some examples please! I’ve never heard of plastic springs and I always have heard and figured it was impossible… Please educate me! what gun has ever used plastic springs!?!?!

    • Rev. Clint


    • Pedro C.P.

      Well the leaf springs of the Corvette are a good example of a “plastic” spring. Yeah they are made of a composite GRP (Glass Reinforced Plastic) and not from pure plastic and sure the applications are widely different , but still are an example of a non-metallic spring.

      I don’t know how well plastic and composites would fare in the internals of a gun due to its environment, but by seeing the high-performance automotive world as well as hammers, barrels and other critical components being made of such materials I suspect its only a question of engineering.

      Would it be worth? Depends. You would save weight and get a stronger component for that task and free from corrosion. But would also have a more sensitive, brittle (it can actually be good if you want to dissipate energy…) and mostly likely expensive component.

      Plastics and specially composites are the future, but will never replace metals.

      • Flounder

        Thanks pedro. And after I made that comment I did go online and found every reference I could to plastic or polymer springs. And I now know it can be done. although everything I found seemed to point out that plastic springs deteriorate under a load or with use much quicker than normal metal springs. That’s just how I currently understand it.

        On another note You could print floor plates and bodies of mags then incorporate metal springs and feed lips. Just a thought.

  • 6677

    @S O Home 3d printers can print many materials including cake icing, ceramics and solder as some of the more “exotic” options. Many different plastics work though.

    I don’t think the spring used in the original was created by the designer and as such wasn’t his to put in the download file. The makerbot website has many spring designs several of which match the one used by the designer and this is likely where it was from.

    • Mount

      Posted by Crank on Thingverse:

      >I left my printed spring design out on purpose for saftey reasons.

      • 6677

        I do apologise then.

        Regardless the end user can print his own springs

  • Mount

    The technology to print usable gun parts exists and has been around for a little while, it’s just expensive. The ability for the hobbyist to do it at home is just starting to become a reality. I’m sure that a tinkerer with enough experience, and who has invested probably at least a few thousand into his printer, could build a magazine of decent quality and durability. The printed spring is only there for the novelty of a %100 printed magazine I think. Add a cheap spring from the hardware store, salvage from another mag, or make your own to fit and this would probably work fairly well.

    Just give it a few more years, the technology will get there. Remember when CD burners first came out? Now what computer doesn’t come with a DVD R/W?

  • Mount

    Here is another one made by Pointedstick of Thingverse using the same design. Seems to have pretty good resolution, and it looks like the rounds fit fine. Also, peeking through the hole in the side it looks like he used a real spring.


    It seems like it would hold up, I just wonder how the feed lips would withstand the abrasion of cycling a few hundred rounds through.

  • Samopal

    I don’t know much about 3d printing, nor am I sure printing gun components at home will catch on anytime soon, and I AM grateful that someone tried this…but this test doesn’t look like it means anything.

    Donald said the ABS he used is known to shrink ~2%, so it should be no surprise that cartridges fit properly. Who knows how it could’ve worked with another type of plastic?

    All in all I’d like to see this attempted with a suitable material. The only thing this proves is that the magazines aren’t as pretty as the designer lets on.

  • Bandito762

    A plastic spring may work for awhile but a loaded plastic spring would relax pretty quickly and eventually not put enough pressure on the rounds. It would also fatigue fairly quickly and break.

  • Cymond

    If someone is serious about using printed mags, it would be possible to design separate bodies & feed lips, and just print new lips as needed.

  • crank

    As the person that designed this magazine. I have a few things to say. First off I made a plastic spring just for the challenge of it and to make the whole magazine “printable”. Yes, a metal spring is superior…..by far.

    This is definitely not for the light of heart for printing you need a finely tuned printer to do it. I did mine on my UP! The reason I left the spring out was for starters a safety reason. No matter what I believe in the right to bear arms, I would hate for some punk kid/adult to print this out use it for some horrible reasons, instantly. I took another step of not posting the spring so one has to experiment with it, etc… Also different printing settings, feedstock materials, etc.. would yield possibly different spring rates. What spring might work on mine may not work for you.

    People have way overestimated the design or perhaps I didn’t state it enough in the following posts on thingiverse. This is just a simple mag not something I would take to a “firefight” nor is it even comparable to a P-Mage However, if I had a choice between this mag loaded vs. no mag at all for my AR…..I would take this one. I posted this design to illustrate the profound revolution that is going on in low cost 3-D printing and what can be made with them. Think of it this way no government can take this mag away, when you can print one yourself.

    There is a design errata that I found with the current design, with the mag catch release location on the mag it is too high on the mag not allowing it seat closer to the bolt on some models. I need to release a new version addressing that issue.

    With all of that being said I welcome your comments, suggestions, etc…

  • Netforce

    Is this even reliable?

  • greensoup

    I’m surprised it took this long for someone to try it. I’m wondering if you could do a reverse print and use the 3D printer to make a mold for casting and then use some type of resin and make your own.

    Or use a low cost CNC machine to cut them out of blocks of plastic.

    • 6677

      Might be able to, but the melting point of the material to be cast would have to be quite low as 3D printed plastics aren’t exactly astonishingly high melting points.

      CNC machining (as well as other material removal techniques) obviously give large amounts of waste scrap. 3D printing gives no scrap with the exception of the occasional support beam for overhangs, even then the supports aren’t massive and are less than CNC scrap, the few 3D printers that feed from pellet hoppers can be fed scrap aswell as you simply break the support into small chunks and throw it in the hopper.