|Manufactured:||2010 (First appears in Halo Reach)|
|Range:||Medium to Long|
|Type:||Bullpup select-fire battle rifle|
The M392 Designated Marksman Rifle, more formally known as the Designated Marksman Rifle, Caliber 7.62 mm, M392, and commonly known as the DMR, is a select-fire rifle used by the United Nations Space Command.
The M392 Designated Marksman Rifle is an air-cooled, magazine-fed, gas-operated select-fire bullpup rifle that fires 7.62×51mm ammunition from a fifteen round detachable box magazine; the weapon's design aesthetics resembles those of the BR55. The weapon has a fire mode selector switch above its grip and a mounted optic with 3x magnification. The M392 has an ambidextrous magazine release button located directly above its magazine well just behind the trigger, as well as ambidex-friendly safety & firing mode controls - however it does not feature an ambidextrous ejection port, making use by left-handed shooters extremely difficult if not outright impossible (as hot shell casings would be ejected directly into a left-hand shooter's face). In-universe, the 7.62x51mm ammunition is interchangeable with ammunition from both the MA5 series of Assault rifles and the majority of the UNSC's light machine guns (such as the M739 SAW or the turret-mounted machine gun used by the Scorpion).
The DMR is an excellent sniping weapon. Landing headshots from vantage points is easy because its semi-automatic mode minimizes recoil. The DMR has the range of a Sniper Rifle and a higher accuracy and larger ammunition capacity than a Magnum (at the cost of reduced fire rate). The DMR kills a SPARTAN-III with full body armour in four body shots and a headshot. The large size of Elites makes them easy pickings. The DMR is stealthier than the Sniper Rifle because the DMR leaves no trail of smoke.
The Designated Marksman Rifle is not without its drawbacks. Due to its semiautomatic fire rate, it is a substandard weapon in close quarters combat. Additionally, each magazine holds only 15 rounds, resulting in frequent reloads during which the user is vulnerable to attack. Finally, ammunition for the DMR is scarce, and the maximum carrying capacity is low at only four reserve magazines, making ammunition consumption a constant worry. A player can compensate for these disadvantages by carrying a close-in combat weapon (preferably with common ammunition), but will still need to watch his ammo meter carefully, especially if he or she favors long-range combat.