M78 phased-plasma infantry gun (Earth-5875)

The M78 phased-plasma infantry gun (PIG) is a man-portable anti-armor directed-energy weapon developed by Misriah Armory and used by the UNSC Marine Corps. Its main ammunition is a form of vaporized plasma laser able to burn through armor.

Operation
The M78 consists of two parts: the launcher and its power pack, which together weigh 15.2 kg. The gun itself is a 15 mW phased-plasma system that fires vaporized cadmium telluride pellets from a 30-round feed. The fast-discharge system powering the gun's laser and magnetic coil is fed from a 4 mW hydrogen fuel cell in the power pack. The firing cycle takes 3 seconds, most of which time is taken up by the powering up of the discharge generator.

The weapon's penetrating power is considerable, and it is claimed to be able to breach the flank armor of a M808B Scorpion tank at 1,000m. However, many Marines show disdain for the weapon's considerable weight, and prefer the more conventional M319 grenade launcher and the M5 RPG despite their reduced anti-armor capabilities.

Source

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