M40 HEDP grenade (Earth-8573)

The M40 High Explosive Dual Purpose (HEDP) grenade is an volatile fragmentation grenade manufactured by Armat Battlefield Systems and used by the UNSC Marine Corps as ammunition for the U1 grenade launcher.

Overview
The M40 is primarily designed to be fired from the U1 grenade launcher attachment for the M41 series of rifles, although it can also serve as a hand fragmentation grenade. The cartridge consists of two main sections - a rimmed, separating base and a metal casing topped with a red plastic identifying cap. When fired from a U1, the base propels the casing from the grenade launcher's barrel with a muzzle velocity of around 78 m/s. The grenade round has an effective range of 400 m, and an accurate range of around 180 m. The projectile itself contains notched steel wire wrapped around a Composition B15 explosive core, which spreads more than 300 metal fragments over a casualty radius of 5 m upon detonation.

Despite its main purpose as a launched projectile, the M40 can be employed as a hand-thrown grenade by flipping off the red plastic cap and depressing the button beneath. This will trigger a three second fuse, after which the round will detonate.

Trivia

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