BR55HB battle 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 Halo: Arms Race) 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. The main difference is that the BR55HB SR Battle Rifle has a slightly longer barrel.

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 charging handle (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
It is interesting to note the ammo used for the Battle Rifle. It uses a new 9.5mm x 40 Experimental Round. The 7.62 x 51 mm NATO round is a rather high-powered round used on the MA5B and on modern-day marksman rifles and machine guns. The 7.62 mm already has a history of having too much recoil because of the rounds high power, which made it hard to fire fully-automatically in assault rifles. While the BR55's larger 9.5 mm round would be heavier and would thus presumably generate even more recoil than the 7.62 mm NATO, this is not necessarily the case. Since the Battle Rifle's rounds have a noticeably shorter case length than the 7.62 mm NATO (40 mm vs. 51 mm), they most likely contain much less powder than the 7.62 mm NATO, which would yield less muzzle energy and thus less recoil, making the weapon more manageable.

However, the size of the ammo would have a problem fitting in the 36-round magazine of the current Battle Rifle. If a Heckler Koch G3 (which is chambered in 7.62mm x 51) has a standard magazine count of 20 and be the size that it is, it would be hard to see a cartridge much wider than the 7.62mm fit inside of a magazine of the Battle Rifle's size and with a capacity of 36 rounds. The Battle Rifle's magazine would have to be about twice as long as it actually is to hold that many rounds. This is a continuous pattern with UNSC assault rifles as a similar instance occurred with the MA5B. The MA5B has a magazine of 60 rounds chambered in the 7.62mm x 51 with a rather "small" magazine size, which looks to be smaller than the Battle Rifle's magazine.

Note: Please see discussion about the further speculation about this ammunition at http://halo.wikia.com/wiki/Talk:BR55_Battle_Rifle

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 (X)M8 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.
 * This weapon fires very similarly to the Heckler & Koch G36/AR15 which fires using the Short-Stroke Gas-Operated Rotating-Bolt, aside from the fact that most trigger assemblies for the G36 use a two shot burst.

Related Articles

 * BR55 Battle Rifle