So, we need PCBs, the high voltage capacitors, we also need Thyristors. We need some infrared LEDs and some phototransistors. We also need some BJT transistors. The rest are some resistors and some LEDs. We also need the copper coils. To make these you can download from below my 3D design. Remove the supports and you will be left with a basic support. Then you can add around 150 loops using thick enameled copper wire (0.8-0.9mm) that could withstand enough current. Once you have all the loops, you can add some KEPTON tape on top so the coil will stay that way. Or if you think that’s too much work, you can find these coils to buy on the internet, see below. We also need some powerful diodes and some push buttons to fire the gun. On the other side we need the high voltage module and maybe a 3S battery or even better a battery socket. As projectiles I will use some 6 to 7mm metal rods that you could cut to around 2cm and maybe smooth the edges. As the gun barrel, I will use an 8 mm metal tube. It would be better to use a plastic tube so there would be less magnetic attraction and less friction with the bullet. You have to make holes on this tube from side to side