Meh, Lucky. My EM-CC (Electromagnetic Compressed Combustion) Bolt action cannon cost me the latter side of $500, including case construction, plans, cutting, internals, microcontrollers, etc.
I haven't posted any pics of it yet, as it was a old design. I lost the plans to it, have it locked up in the closet, and I only have one more box of ammo left for it, but it was HELLA AWESOME.
I wonder if it still works. Lets see...
Argh, the battery's dead. Figures. I've had that dangerous thing locked up for 2 years now since it knocked down a small tree.
BTW if you want to know how it worked, it was a parallel circuit, controlled by a PIC-1 microcontroller (I think it was named that), with half the electricity going through a compressed cartrige with air and propane in it. The other half, or rather, 70%, went to the coil wrapped around the barrel, made out of ABS. Due to the fact it shoots iron, it is not a spud gun.
I'm severely bad at pneumatics. That's why I made a noobish topic about pneumatics, but electromagnetics are a different story.
Pneumatics, I'm experimenting with cheap substances. Electromagnetics, I am trying to make a more ergonomic, semi-automatic design.