The plasma rifle uses microfusion cells, the same type of ammunition used by the laser rifle, and can discharge up to twelve green, self-illuminated plasma bolts before requiring a reload. The plasma rifle can fire a total of about 500 shots, the equivalent of 42 reloads, from full condition before breaking.
The plasma rifle fires projectiles that inflict potentially heavy damage at a fairly quick semi-automatic rate of fire. The plasma bolt moves at sub-sonic speeds, giving enemies the chance to dodge the plasma bolts. Because of this, the plasma rifle is most effective in close to medium range combat, as opposed to the laser rifle, which is better suited to long range. Due to its fast semi-automatic rate of fire, it empties its 12-shot magazine rather quickly, and its reload time is somewhat longer than most other small guns/energy weapons. Maintenance is a combination of perks and drawbacks: Like other energy weapons, it has a high maximum condition compared to small guns, but is expensive and/or difficult to repair. A plasma rifle in poor condition (under 10%) can cost over 1,000 bottle caps to repair. The plasma rifle has twice the chance of inflicting a critical hit than most other weapons, and can turn enemies into piles of green goo if the killing blow is a critical hit. Like all energy weapons, the plasma rifle's plasma bolt can ignite gas leaks.
Plasma rifles or plasma casters are high-tech weapons which find numerous applications in military and industrial fields. They fire superheated bolts of plasma powered by either microfusion cells or heavy energy cells. The bolt forms in a special chamber, which is then sent down a superconducting barrel, propelled by, and in some models stabilized by electromagnetic claws upon exiting it.
Initially, the weapon was a bulky, industrial plasma caster, manufactured by Winchester Arms; while it performed admirably, it was expensive and required specialized training to use. However, later developments for the US Army would lead to a more compact design that was cheaper to produce and easier to train for, perfectly suited for urban warfare.
Regardless, all types of plasma weapons have a common feature: when a critical hit is delivered, they can literally melt down enemies. While most industrial casters aren't powerful enough to dissolve bones too, subsequent models have no problem converting the target into a puddle of goo.
This plasma rifle is a lightweight urban warfare weapon created by REPCONN Aerospace for the US Army based on engine parts from the failed Z43-521P - "Green Bean" plasma-powered rocket. Like the AER9 laser rifle, it uses a microfusion cell as its power supply. It taps into the cell, essentially a small fusion reactor, to produce a toroid of plasma that is ejected down a superconducting barrel. In contrast to the Winchester P94, it does not have the electromagnetic claws.
As of 2277, these plasma rifles can usually be found in use by Enclave soldiers on the East Coast. By 2281, they can be found less commonly throughout the Mojave Wasteland. [Source: wikia]
You can download the papercraft model template here: Fallout 3 - Life Size Plasma Rifle Free Paper Model Download