- "The M6 has been in service for about a hundred and forty years… it’s amazing to think how little it has changed in all that time."
- —Anonymous UNSC serviceman
The M6 Personal Defense Weapon System is a series of short-barreled weapons produced by Misriah Armory.
The M6 series have seen major widespread distribution through the UNSC Defense Force as lighter firearms, although they are not always seen as primary weapons, because of their lighter penetrating power. They have seen usage in the UNSC for almost 140 years. Common slang terms for the M6 series handguns include go-mag, hand cannon, and power drill.
 Design details
The M6 series weapons are recoil-operated and magazine-fed, and typically fire 12.7 x 40mm projectile ammunition, and despite the large caliber, often times "exotic" ammunition is not utilized. They are also remarkably large and overpowered to an extent, appearing to be redolent of a cross between a pistol and a rifle in size. In addition to power, the M6 line of weaponry is designed to be exceedingly rugged and reliable, and the guns are able to remain operational after Slipspace transitions and high-g aerial maneuvers, as well as the rigors sustained during standard combat. However, the heavy weight limits its distribution amongst personnel, and the M6 weapons have a tendency to drop casings on the wielder's foot, leading some UNSC personnel to favor the M7/Caseless Submachine Gun which operates on a caseless system.
They have remained remarkably unchanged during its decades of service, although there are a large number of variants. The M6 series handguns are issued in three different finishes: hard chrome, black polymer, and electroless nickel. Some variants of the M6 series have been 'up-sized' to approximately 117% their normal size to better facilitate use by Spartans.
 Known models
- M6A - Used mostly by civilian security forces, standard issue/black polymer finish.
- M6B - Used mostly by civilian security forces, KFA-2 x2 scope, hard chrome finish.
- M6C - 'Up-sized', armed with High Penetration ammunition, black polymer finish..
- M6D - 'Up-sized', armed with High Explosive ammunition and featuring KFA-2 x2 scope.
- M6E: standard issue/electroless nickel finish.
- M6F: smart-linked scope KFA-2/electroless nickel finish.
- M6G - 'Up-sized', smart-linked scope KFA-2, armed with High Explosive ammunition and electroless nickel finish.
- M6H: 'Up-sized', smart-linked scope KFA-2/electroless nickel finish.
- M6I: select-fire variant; detachable shoulder-stock/black polymer finish.
- M6J/C - UNSC Army carbine variant. 355mm barrel, detachable shoulder-stock/electroless nickel finish.
- M6K: police 'undercover' variant; 6 round magazine capacity/black polymer finish.
 UNSC personnel remarks
"The M6 is either the world’s biggest pistol or the world’s smallest rifle — I’m not sure which."
"It’s strange. Normally a big bore means access to a greater variety of exotic munitions, but we just don’t see that variety in the field."
"The M6 has been around forever; the number of variants and configurations is dizzying... have you ever seen an M6J(C) — the Army’s carbine variant?"
"The M6 has been in service for about a hundred and forty years... it’s amazing to think how little it has changed in all that time."
"The longevity of the M6 has always been more about pork barrels and Slipspace travel than reliability or the so-called brilliance of its design."
"The A's and B's are way more comfortable to shoot, but you don’t see many of them outside of civilian security forces anymore."
 List of appearances
- ^ a b c d Bungie.net: M6g Personal Defense Weapon System "The M6 has been in service for about a hundred and forty years… it’s amazing to think how little it has changed in all that time."
- ^ a b c d e f g h i j k l m n Halo Waypoint: Magnum
- ^ Halo Encyclopedia, page 307
- ^ a b c d e f g h i j k l m Bungie.net: Halo 3: ODST Project Page