7.62x51mm

A 7.62x51mm cartridge.

The 7.62x51mm cartridge is an ammunition size in which the rifles and machine guns of the United Nations Space Command are commonly chambered. A significant variation of ammunition types for this cartridge are employed.

Overview

This cartridge shares its dimensions with a form of rifle ammunition developed in the 20th century, employed commonly across the nations of the North Atlantic Treaty Organization under the designation 7.62 NATO.^[1] The UNSC employ it in a wide variety of weapons, including:

The MA5 series assault rifles, including the MA37
The M392 and M395 Designated Marksman Rifles
The M739 Light Machine Gun
The M247 General Purpose Machine Gun and M247T Medium Machine Gun

Weapons chambered for 7.62×51mm ammunition, such as the MA5B assault rifle, are considered to be powerful by UNSC soldiers.^[2]

Variants

M118 FMJ-AP

M118 FMJ-AP (full metal jacket, armor-piercing) rounds are the standard-issue ammo type employed by the UNSC's assault rifles,^[3] the M392^[4] and M395 DMRs,^[5] and the M739 LMG.^[6] The round's armor-piercing capabilities stem from its specially hardened construction.^[2] UNSC infantry combat armor is capable of preventing lethal penetration at close range from a limited burst at the cost of bruising and significant discomfort,^[7] though infantry and even light vehicles or aircraft such as un-shielded Covenant Banshees are susceptible to fatal damage under sustained, accurate fire.^[8] Energy shields drastically reduce the ammunition's stopping power, as a great deal of concentrated fire from multiple weapons - or an extended period of continuous automatic fire from a single weapon - is needed to overwhelm them.^[2]

Gallery

An M118 ammo pack in Halo: Combat Evolved.
A packet of M118 ammunition.
A 7.62x51mm bullet extracted from Zhao Heng Lopez's shoulder in The Mona Lisa.
Closeup of an 7.62x51mm AP cartridge in an MA5D's magazine in Halo 4.
A round of 7.62x51mm AP ammunition seen in its magazine in Halo 5: Guardians.
7.62x51mm shell casings ejecting from a firing MA5D in Halo 2: Anniversary multiplayer.