The M90 Close Assault Weapon System is a pump-action shotgun used by the United Nations Space Command. Part of Weapon System Technologies' DTM series, the M90 is a copy of Misriah Armory's M45 Tactical Shotgun.
The M90 CAWS is functionally identical to the M45E on which it is based. It is chambered for 8 gauge ammunition, typically the Soellkraft 8 gauge magnum in lieu of the M296 Magnum used by the M45. The cartridge provides immense firepower and ease of use with little risk of penetrating spacecraft hulls. The weapon features a dual-tubular, non-detachable magazine that can be fed up to twelve shells through a top-mounted elevator. As the M90 is pump-action, spent shells are ejected each time the user works the action.
A tactical flashlight is mounted in line with the action shortly behind the muzzle. The iron sights may be colored faint blue (like the M45E's) or vibrant green. The weapon has an adjustable stock.
The M90A variant is similar in performance to the original M45, whereas the basic M90 is patterned after the M45E. The M90A has a magazine capacity of six shells rather than twelve, though this is compensated for by a longer barrel. The tactical light is mounted on the left of the action's grip instead of in front. The iron sights are colored blue.
Shotguns saw prominent use during the frequent close-quarters urban combat of the Insurrection. Misriah Armory's M45 Tactical Shotgun (particularly the M45E variant) was acclaimed by its users, prompting Weapon System Technologies to develop a more economical and practical version. The resulting M90 Close Assault Weapon System is part of WST’s DTM series, which is also marketed to civilians and law enforcement agencies. Over the next several decades the M90 eclipsed the M45 in both the military and the private sector, seeing widespread use during the Human-Covenant War. However, both models continue to serve alongside one another, particularly in the UNSC Marine Corps. Jiralhanae on Installation 05 used captured M90s (along with other UNSC weapons) at the outbreak of the Great Schism. The weapon was one of many featured in the report Machines, Materiel and Munitions from the Human-Covenant Conflict, 2525 - Present.
The M90 has earned a plethora of nicknames over the course of its service life, including "waste 'em", "deck clearer", "The Hammer", " Mop", "Broom", "Universal Translator", "High Stick", "Thunderer", "Betsy", "Equalizer", and "Okay-47".
The combined force of each of the fifteen spreading pellets per shot does a significant amount of damage against almost any type of infantry at close range, and the shell's widespread in certain situations can inflict shrapnel damage to multiple infantry. A near miss can still inflict grievous damage; the M90 Shotgun's powerful 8 gauge shell can punch through armor and Energy Shields easily, making the M90 a great weapon for taking on heavily armored infantry and lightly armored vehicles. The M90's top loading system allows a user to reload the shotgun with speed and ease for quick firing.
While extremely devastating at close quarters combat, the M90 is rendered virtually useless at extreme ranges, and should therefore be used in conjunction with a medium or long range weapon. The shotgun's pattern is extremely loose, and fans out quickly, thus at farther ranges, only a few pellets out of the 15 might hit. The M90, being a pump action shotgun, must be reloaded after every shot before it can be fired again, so a user missing enemies may as well be a death sentence; the M90 must also be reloaded shell by shell and does not use any type of external magazine. This can make reloading time-consuming when in combat situations, but it is useful to be able to interrupt the reloading and shoot after you load a shell. In close-quarter situations, the wide spread of the shell can potentially harm friendly infantry if the shotgun is fired indiscriminately.
List of appearances