It appears the era of potato guns has come to a swift end: Redditor and DIY wizard NSA_Listbot just built a portable, 3D-printed railgun. The device, which uses electromagnetic energy rather than gunpowder, was so complicated it required an AutoCad mockup, and fires projectiles at a whopping 560 miles per hour. We’re going to throw this one into, “things you probably shouldn’t even think of at home.”
The device is powered by six capacitors, which weigh a combined 20 pounds, and a battery that can produce 1,050 volts and over 3,000 joules of energy per shot. “It isn’t likely lethal, but it would definitely hurt,” says Listbot (that’s comforting), who tested his creation using an array of materials including carbon graphite, aluminium, teflon, and copper-plated tungsten.
The physics behind the gun is actually quite simple: an electric current is sent down one of two parallel rails (hence the name), across the projectile, and then back down the other. A magnetic field between the rails pushes on the current, which is now running through the bullet. The bullet advances forward, now at speed, to be accelerated again and again. It’s this interaction that fires the gun.
Dangerous as it may be, our new overlord has gone to great lengths to ensure his railgun is as safe as possible – it is far less powerful than military-grade prototypes, which can generate three-thousand times more energy (over 10 million joules) than the DIY version:
Listbot’s electronics are based around an Arduino Uno R3, which monitors voltage and temperature to ensure even charging and stability. Along with the capacitors, an emergency discharge, power resistor, and a button to dump any energy leftover after a shot, are housed within the 3D-printed frame.
It’s undoubtedly a menacing piece of machinery, but we’d take our chances with it over this DIY laser gun, or this DIY magnetron. Check out more images from NSA_Listbot in the gallery below. View the complete design here.