I am finally done with my BR, now enjoy some lore dump about the Rifle.
The BR55 Heavy Barrel Service Rifle (BR55HB SR), also known as the "Mammoth Stomper," is a select-fire rifle utilized by the United Nations Space Command and manufactured by Misriah Armory. It is a heavy-barreled version of the BR55 Service Rifle.
The BR55HB SR entered service in 2548, serving alongside the standard BR55 Service Rifle. For decades, the BR55 had steadily gained favor over the long-serving M392 Designated Marksman Rifle. The introduction of the BR55HB SR led to an immediate increase in the BR55's popularity, prompting all branches of the United Nations Space Command armed forces, except the Army, to replace the M392 with the newer weapon.