Thread: Mags

I have 3d printed a bunch of mags for various different rifles, center-fire and rimfire. I have found it generally takes at least 5 or 6 versions to get the geometry perfect, and that is with an existing magazine to copy. The next hardest part is making or buying a spring, again it helps to have an original on hand to copy and measure. After that, material selection is important. You need a very stiff yet tough material for center-fire magazines, especially relatively small mags that cram lots of rounds in. Single stackers are easier than double stack single feed. Good quality ABS is fine for rimfire mags but you will probably run into stiffness issues in the feed lips for center-fire mags. I have found nylon to be too flexible, even when carbon reinforced. I have done a little experimentation with Carbon PETG and that seems promising.

For rectangle coil springs (most modern mags) you can get spring wire from hobby stores and bend it with a couple of pairs of needle nose pliers. It takes some time and practice but you can get a usable spring. This type of spring will take some set eventually if it is over compressed and will lose its "spring" your better off purchasing something off eBay where there is a huge variety of rectangle coil springs available very cheap. But it's good to make a few by hand first to get an idea of exactly what dimensions and wire size you need.

If it is a leaf type spring, they are much harder to make and source material for as the spring thickness and width has much more impact on the spring rate, so must be more accurate.

If you don't have the knowledge and access to a CAD system and 3D printer, it will cost you a fair amount of $$ to get someone else to do the design and testing for you, there is a lot of time involved in getting 3D printed magazines to work properly. Saying that, once the design is sorted and a commercially available spring sourced, they are piss easy and cheap to make.