BR55IA FA Battle Rifle

The BR55IA FA Battle Rifle, or BR55 Interchangeable Attachment Fully Automatic Battle Rifle, is a variant of the BR55HB SR Battle Rifle, a weapon designed to be able to fire fully automatic and support a wide variety of attachments.

Physical Appearance
The BR55IA FA is a bullpup, fully automatic, UNSC rifle that fires the 9.5x40mm X-HP-SAP round. 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 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 BR55IA FA is externally almost identical to the standard BR55HB SR. The only noticeable differences are the attachments that it frequently has put on it; it is standard for it to have a laser sight on one side of the front end of the weapon, and a flashlight on the other. It can also have red dot sights, iron sights, or digital imaging sights affixed on the optic rail. Internally, it features the mechanisms needed for a fully automatic weapon, but also has a more complex digital suite embedded in the weapon.

The BR55IA FA has a rate of fire of thirteen rounds per second, and seven hundred and eighty rounds per minute. It has a higher rate of fire than the MA5C, which has a rate of fire of seven hundred and fifty rounds per minute, or twelve point five rounds per second. The BR55IA FA has a higher damage per round than the MA5C, as it has the same damage amount as the standard BR55HB SR. It is slightly less accurate than the BR55HB SR, but is still more accurate than the MA5C, especially when fired in burst. The BR55IA FA has a large amount of recoil, which means that fully automatic, it is especially difficult to aim.

Development
The BR55IA FA was developed in late 2552 directly after the First Battle of Earth. It was rushed through production tenfold, in order to be ready for the inevitable Second Battle of Earth. It was made alongside the BR55HB SR, which was also quickly developed after the First Battle of Earth. The goal of the BR55IA FA was to create a BR55 that was able to be modified and that could fire fully automatic, something the original BR55 or the BR55HB SR did not allow. Unfortunately, not many of the weapons were able to be produced in time for the Second Battle of Earth. This was due to a limited amount of facilities able to produce the weapon, and a high cost per rifle.

Changes From The BR55 and the BR55HB SR

 * Laser sights mounted on front end of the weapon
 * Fully Automatic
 * Higher Recoil
 * Modular Sights
 * Lower Accuracy
 * Flashlight mounted on front end of the weapon

Field Usage
The BR55IA FA was seen in combat only once: the Second Battle of Earth. It was used throughout the planet, and notable persons who used the weapon were T. Rymann and S. Hartley, who sent coordinates to the Sierra 117 (John-117) recovery team. The weapon was demonstratively better than the MA5C, having a higher rate of fire, more damage, and more accuracy, but to few of them were created before the battle to make it a widespread weapon. During the battle, it performed exemplary, and it allowed marines and ODSTs to gain higher kill to death ratios. However, after the battle, the BR55IA FA was deemed unnecessary, and it was discontinued.