Gadulo-pattern needle rifle

The Type-31 Needle Rifle, also known as the needle rifle, is an infantry weapon variant of the needler originally manufactured by the Covenant's Sacred Promissory, formerly in service with the Covenant Empire's military. After the fall of High Charity in 2552, Maeleesh Bazaar took over the production of the needle rifle. The needle rifle is depicted being used by Sangheili, Jiralhanae, Kig-Yar, and Yanme'e. The number designation "Type-31" is simply a numerical designator that aligns with the year this particular permutation of the needle rifle was first encountered by the UNSC; the year 2531, hence the "Type-31" designator.

Design details
The Type-31 Rifle fires unconventional, long and razor sharp projectiles made of blamite. The projectiles detonate several seconds after coming to rest in soft tissue. The rear end of the weapon appears to be on a hinge, indicating it may be able to collapse into a more compact form.

The needle rifle is a fully automatic, short- to medium-range rifle, similar in many respects to the Covenant's Type-51 Carbine. Unlike the Type-33 Needler, the needles do not "home", or track on the enemy. They fire in a straight line at high velocities, similar to the M392 DMR. Rounds travel much faster than that of the needler, leaving the needle rifle's only destructive similarity to the needler being the individual/collected needle explosion.

The reload process for the needle rifle is very similar to that of the Covenant carbine. The scope for the weapon acts as a hatch, which flips open to expose a small canister that ejects upon opening, and a new canister is inserted by the user. The only difference between the reloads for the Carbine and the needle rifle is that the canister for the Carbine is not covered by any sort of hatch, which in the case of the needle rifle is its scope. This reload process implements another difference from the needler, which actually summons new needles from the inside of the weapon through the operation of what is suspected to be an internal mechanism.

Trivia

 * The scope of the needle rifle has a hash-mark compass. To the right of the scope, it also features a symbol which turns red when the crosshairs are aimed at an enemy.
 * Kat-B320 was killed by a needle rifle shot to the head. Unusually, the round went straight through her helmet instead of sticking and detonating on the surface.
 * Killing an opponent with a supercombine of the needle rifle's needles will grant the player a Needle Kill Medal.
 * During the Halo: Reach Beta, the needle rifle had an 18-round magazine. This was increased to 21 rounds (to match the three round increase in the DMR's magazine size) for the final game, but the render of the weapon wasn't updated, so a fully loaded needle rifle will still only show 12 needles sticking out.

List of appearances

 * Halo: Reach
 * Halo: Glasslands
 * Halo 4: Forward Unto Dawn
 * Halo: Spartan Assault
 * Halo: Escalation
 * Halo: Shadow of Intent
 * Halo: Ground Command
 * Halo: Retribution
 * Halo: Fireteam Raven