Welcome to the Future: Print Yourself an AR-15 Magazine at Home!
My dreams have come true. It is now possible to use a desktop 3D printer to print an AR-15 magazine, floorplate, follower and spring!
The 3D models have been opensource, so anyone can use them, modify them and distribute them. All you need a MakerBot desktop 3D printer. The latest MakerBot is sold in kit form for $1,299.
An AR-15 lower receiver 3D printer model has also been published, although nobody has published photos of the end result.
Do any TFB readers have a MakerBot or similar printer?
[ Many thanks to Steve for emailing me the link. ]

$1,299 would buy a crap load of proven metal mags, and ammo to stuff them with!
The thing that wears out metal springs and causes them to lose power is repeated use. They’ve found old magazines that were loaded during WW II but they still functioned. Someone needs to load up some plastic sprung magazines and see how long they held out. If you get your mag costs low enough the magazine becomes a disposable item. If the new poly case ammo works out you could have a pretty light load out.
Someone needs to start with a clean new gun design to take advantage of the 3D printing process.
You have to be careful with those schematics from Thingverse or watch your ABS. I know of a guy who printed out the magazine and found that he could only fit one bullet into the magazine because either he or the design didn’t account for ABS shrinkage and the overall length of the bullet is too long for the magazine.
Another 1mm or so might do the trick and rescaling the magazine by 2% to 3% should provide some tolerance.
Ive Actually Seen A Printed Lower Receiver. From Magpul..
3D printed AR mag: $1299.00 to get the kit.
AR mag in gun store: $10.00
Guess I’m off to the gun store..
Cymond: You have to load the printer.
Really, it’s exactly analogous to a CNC mill making a lower from billet stock; someone sets it up and presses the button.
That’s them making it.
If there’s a “nobody can help” requirement, it’s trivially satisfied by loading and prepping the machine yourself (and doing any cleanup or finish work like drilling, also by yourself).
I’ve been thinking about building a 3D printer for a while. It looks like a huge amount of fun, and endlessly useful for the home tinkerer. With some 3d modeling/computer drafting skills you could make replacement parts for all kinds of stuff!
I’ve read that the guy who designed that magazine had successfully tested it on his friend’s AR. I wouldn’t use that spring except for the quick novelty of a fully printed mag, I’m sure anyone could scrounge/make a real spring with out much trouble.
Did see a guy make an AR lower out of cutting boards, and it tested well.
I…think I’ll wait for some QC on this. I know there are springy plastic polymers out there, but if I wanted high-cap mags I’d feel much better if I could gut it and find a metal spring feeding in rounds. I wouldn’t want to try out using a mag speed loader or just feeding in rounds to capacity, then hear a loud snap, remove the bullets and find plastic shards pouring out of the magazine.
@Jdun1911
Take a look at the reprap website and they have a whole wiki’s worth of information regarding building a reprap from parts, where to buy kits instead, where to get the material, what materials can be used, various options regarding different configurations of printer, user created variations on the reprap (the design and software are open source) and how to use your printer with the different materials, it is a very good resource.
Reprap is an open source 3d printer design, the makerbot is based on the reprap and many reprap users claim the maker bot is inferior to a PROPERLY BUILT reprap, your first home built reprap or a cheap kit might not possess the accuracy to print a usable magzine without taking files to it but a more expensive one or some high quality parts (information again on wiki) can actually exceed the accuracy of the material extruders themselves. With the exception of motors, metal guide rods and electronics the reprap can print all the other components to build a reprap, the beginings of self replicating machinery right there in front of you. Materials used are typically ABS or for biodegradable projects PLA. Don’t know how an AR15 made of either material would work but a bio degradeable AR15 would be pretty cool. SOme people have also had success printing with sugar icing, some sort of ceramic material (steel extruder needed) and heavy guage leaded solder, less success with lead free solder apparently
Something no-one has pointed out, you all claim the spring is going to be the failure point and truly I agree BUT the spring looks easily replaceable, if you modified the source model file to have 5 springs printed alongside each mag instead of 1 then when 1 spring loses tension of breaks then you replace it with another, 5 times the lifetime of a single mag, also theres the fact you can print more springs on demand.
@ryan,
You can find the magazine STL files in the first link of the article
http://www.thingiverse.com/thing:11636
scroll all the way to the bottom.
Also please note that the height of the mag catch recess is open to debate. The author Crank had to modify it to make the feed lips the right height.
falnfenix,
Any hint to where I can start looking to built one?
I am an engineering student, and our college uses the MakerBot that your have the link to. I have printed a few things and from what I have done, I would be concerned about the lack of malleability of the spring and the ability to maintain the tolerances necessary for the box part of the magazine, due to it’s size. Although if anyone has an STL or SLDPRT file for this part, I could probably print it out and see how well it actually works.
HAHAHA! TAKE THAT GUN CONTROL!
Try to ban high capacity magazines?
WE’LL JUST PRINT ‘EM!
Amazing stuff! Now lets see some YouTube video of these things being tested.
Once the open source RepRap 3d printer project really gets going, stuff like this should become commonplace.
This is really cool and I hope to see more 3d printing applications.
Personally, if I were going to make magazines, I’d use a standard metal spring. I don’t think I’d ever make a receiver (but then again, there are polymer AR lowers) on a 3d printer, but parts that aren’t under stress like sights, mags, grips, stocks, for-ends, barrel shrouds, and maybe even some trigger parts (if the precision is high enough) would be fair game.
On a tangential note, the AR-15 has almost become an open source gun. Anyone can make it or a variation. All the specs are fairly readily available.
Too bad physical objects can’t just be torrented like software can.
Printing AR lowers raises an interesting point. Currently, it is legal in the US to build your own non-serialized gun as long as it is only for personal use (federally legal, not valid in all states). However, the owner/maker must do all of the work. No one else can physically assist, but there used to be build parties where everyone chipped in on the cost of the fixtures & jigs, and coached/supervised each other.
So, what exactly is the ‘work’ required to print a lower when most of the task is automated? Just clicking ‘print’ in the software? Start the software themselves? Or would someone also need to load the printer with raw material?
Where do I see this going? Serialized gun barrels!
This guy posted photos of his printed lower…..
http://www.m4carbine.net/showthread.php?t=89247
http://www.powerstrokenation.com/photopost/data/721/medium/trigger-lower2.JPG
That just looks weird looks like it was carved out of soap.
The least expensive 3D printer capable of handling ABS I have seen is described at http://www.reprap.org. They run from 350-850 dollars depending on scrounging versus buying complete kits
That settles it. I’m just gonna have to buy a Makerbot.
Pretty cool. I don’t know much about the type of plastic this thing uses, but I can’t imagine that it is much different than those Thermold AR-15 mags. As for the lower, I think that would be legal as long as you dont try to sell it.
Ok, this is about 20 different kinds of cool!
I did an internship at a laser welding company and they were using a new tech (to spare a lengthy and technical disruption) that printed in metal. It wasn’t precise enough to make parts yet, because that wasn’t its intended purpose but given time i wouldn’t be at all surprised to see machine capable of printing out parts in steel in the near future
Greetings from Texas,
This is interesting, but I don’t think I will be rushing out to get one of these printers.
People have theorized that you could make an AR lower out of wood, because there’s no stress to the lower.
The guy probably made the spring out of plastic to see if he could do it, I would replace it with a traditional spring. As 3-D printers evolve and lower in cost we’re going to have another Star Trek tech available to us.
It’s been pointed out elsewhere, but 1st amendment+2nd amendment =
the right to print arms.
I expect some lawmakers to take a less inclusive stance, naturally.
while the Makerbot is expensive, you can piece together a 3D printer for around $400 if you look around. it’ll take a more hands-on approach, of course, but it’s well worth it in the cost savings.
wow i could buy alot of Pmags for 1,200 bucks….
If the plastic is strong. It would be a lot easier to get 6.5, 6.8, 7.62×39 magazines.
Imagine the future were you can print lowers for rifles, stocks, BUIS and grips. There could be so many possibilities.
Don’t have A 3D printer, but this guy does, and he posted a pic of the lower he printed.
http://www.flickr.com/photos/neometrix/4383002130/in/photostream
whoops, looks like I was wrong. You don’t have a federal responsibility to register or serialize ar15 lowers in the USA that were produced solely for personal use. you do if you want to sell them later.
Well, I still hope that the legislators don’t jump all over this and leave us in the dystopian world of Charlie Stross’s novel “Rule 34″.
Assuming the lower receiver is strong enough in ABS plastic to make a practical weapon and not just be a toy, I assume you would need to make sure to register and serialise them like you would an 80% lower.
That’s the law if you want to avoid a felony, right?
I really hope that this technology is used responsibly and doesn’t get jumped all over by the legislators.
noob,depends on the state law. In some states it does not have to be serialized if its for personal use (not for sale or transfer) and you are not taking it out of the state.
I’ll pass on that spring…
Yes. I have a makerbot printer. It is neat to see this. However, strength and other properties of the magazine will vary on a printer by printer basis due to the various printing options. I would not want to be the first person to try a gun part I print on my makerbot!
I heard of a 3D printer back in high school but the things it printed were not durable in anyway. And is that squiqly thing supposed to be a spring? How could that possibly work?
Absolutely! How do you think companies evaluate designs from a prototype standpoint. You can typically print these parts from a number of local vendors and get them faster and cheaper then machined metal.
Ok, not gonna lie…that’s really f***ing cool.