BR55 Heavy Barrel Service Rifle

The BR55HB SR Battle Rifle is an United Nations Space Command infantry firearm and a variant of the standard BR55 Battle Rifle.

Introduction
The BR55HB SR Battle Rifle is a variant of the Halo 2-era BR55 Battle Rifle introduced in Halo 3. It is a good, all-around weapon and is virtually identical to its predecessor in terms of performance. This weapon is available in Halo 3.

Summary
The BR55HB SR Battle Rifle is a gas-operated, magazine-fed, mid-to-long range weapon capable of semi, burst, or automatic fire. Due to difficult aiming caused by fully automatic fire, both variants have been restricted to three round bursts. It is relatively the same as the BR55 Battle Rifle but with some design changes. It still fires the M634 9.5x40mm X-HP-SAP round in three round bursts (or in fully automatic fashion as seen in arms race, however cannot fire fully auto in actual gameplay, possibly full auto in Halo wars) from a 36 round magazine and it still has a scope with a 2x magnification. Its power, accuracy, and range are pretty much the same as the BR55.

Physical Description and Appearance
The BR55HB SR is a bullpup, fully automatic (Except in Gameplay), UNSC rifle that fires the 9.5x40mm X-HP-SAP round (see below). It fires from a 36 round magazine which fits flush in the receiver. The receiver is built directly into the underside of the butt of the gun and is located behind the grip (known as a bullpup configuration).

This titanium alloy weapon is gas-operated with a rotating bolt and therefore must be cocked before the first round can be fired. The charging handle used to chamber the round is located on the left side of the weapon and does not move during operation. Once the first round is fired, the gases from that round and those to follow impinge upon a gas piston, which pushes back the bolt carrier, rotating the bolt inside and continuing to chamber rounds until the magazine is empty. Once the magazine is empty, the bolt (even though not illustrated in-game) can either be pulled back and locked or, it can be fully cycled after a fresh mag has been housed. If it is pulled back and locked, then it must be pushed forward once a fresh magazine is housed to chamber a new round. The magazine release button is located on both sides of the gun with an arrow pointing down towards the housed mag in the stock. The ejection port is located on the right side of the weapon. There is also a fire selector on both sides of the ammo display.

The BR55HB SR, having a rifled barrel, has noticeable changes from the BR55. First off, it has a longer barrel for increased range and accuracy. It is fitted with a Trijicon ACOG-style scope on a modified carrying handle and now also has a trigger guard. The safety is also located above the handle of the weapon.

Changes From The BR55

 * Modified optical rail
 * New Trijicon ACOG-style scope
 * New trigger guard
 * Longer barrel
 * New reloading animation
 * Less magnetism

Besides these aesthetic/all weapons changes, the Halo 3 Battle Rifle is functionally identical to the Halo 2 version.

Ammunition
The BR55HB SR uses the same 9.5 × 40 mm X-HP-SAP rounds, same as the BR55. See here for more information.

Influences
The BR55HB SR's design is based on the same weapons as its predecessor. It appears to be largely based on the French standard issue FAMAS assault rifle, and also has features resembling the US Army's prototype XM8 (a.k.a H&Ks G36) rifles. Other influences could be the Steyr AUG, the SA80 or the lengthened SA80, the L86 LSW. See here for more information.

Character Compatibility
This is the compatibility of the Battle Rifle in Halo 3.
 * Elites
 * Spartans
 * Marines
 * Brutes
 * Flood Combat Form (Human)
 * Flood Combat Form (Elite)
 * Flood Combat Form (Brute)

Trivia

 * Technically, "HB" stands for "Heavy Barrel" which may hint at a more sustained fire and "SR" stands for "Sniper Rifle" which may also mean better accuracy.
 * In the Halo: Arms Race trailers and in Halo Wars, the BR55HB SR Battle Rifle seems to be automatic. But in Halo 3, however, it only fires in bursts of three rounds. This may just be due to Bungie trying balance the weapon out.
 * The Battle Rifle seems to be a prototype in 2524. Possibly the only people who have them are Staff Sergeant Avery Johnson, Staff Sergeant Byrne, and their two militia marksmen, one of which is the famous Wallace A. Jenkins.

Related Articles

 * BR55 Battle Rifle