Ok, one more destructive gun asked by
. This time the goal was to make a believable plasma gun, so here it is!
The Obliterator Gun (or technically MLIPCC MK I, Military Laser Induced Plasma Channel Cannon MarK I) is a huge bazooka-like device capable of emitting powerful plasma discharges, similar to a natural ball lightning in both power and appearance.
Here is how it works: The Obliterator uses three powerful batteries to produce high energy lasers. In a planetary atmosphere this lasers will overheat the gases and form a tunnel of plasma (high energy ionized gas). A powerful electromagnet is turned on a millisecond after the plasma tunnel was formed, impulsing the high energy matter to the target. The lack of other matter inside the laser tunnel makes the plasma travel in high speeds (220,000 km/h (140,000 mph)), hitting the target as a contained lightning, melting materials (it reaches 30,000 °C (54,000 °F)) and delivering 16 millions volts of electricity, capable to burn all the crew and circuits of a vehicle.
Because of the overheating, it also have a shoulder-mounted liquid nitrogen tank, and several tubes to cool the weapon after and during each shot.
The gun range is limited only by the density of the atmospheric gases. In good conditions (no clouds, no mist or smoke) it can hit a spaceship or a satellite in orbit, in bad conditions the gun range falls for some kilometers, but delivers a more potent blast (more gases to ionize in the laser tunnel).
It can work in vacuum conditions, but them it would use the nitrogen stored in the cooling tanks as ammunition, overheating it inside the laser tunnel.
In atmospheric conditions it can be fired several hundred times, and despite the silence, it's easy to detect the shooter because of the light and nitric acid gases it release (and smell of ozone). In vacuum it can be fired about 100 times before it needs to refill the liquid nitrogen tank.
Modeled in Sketchup, rendered in Twilight, a touch of Photoshop. Information researched in Wikipedia (Plasma, Electrolaser, Plasma Weapon, Lightning, Ball Lightning...)
And yes, US army and Boeing are researching to develop a weapon just like that. By now they can delivers just enough plasma energy to incapacitate a target, like a taser delivered by laser tunnels... at least according to Wikipedia