It's entirely 3D printed, took me about a year to design and build on my Turnigy Fabrikator.
Because the size of the printing area 15x15x10 cm of my Fabrikator is much smaller than the size of the whole thing, I had to glue together the different parts, which in this case was quite challenging, because very tight straightness tolerance was required. To achieve this I used an aluminum beam as reference.
The finished electromagnetic BB gun looks not only cool, but it's also fully functional and basically as good as a normal CO2 powered BB gun.
https://youtu.be/jhtAsYy7dgM
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