This legendary rapid fire-frame sniper rifle is a beast. It has an ultra-light barrel that greatly increases handling speed and stability. It can use ricochet rounds, that ricochet off hard surfaces that adds to the unexpected results, and armor-piercing rounds.
One of the random perks, Rapid Hit, gives it even higher damage when it's quickly reloaded after the kill. You could also get a larger magazine, but the best perk on this beauty is probably Genesis. It can potentially fill its magazine from reserves after breaking a combatant's shield, which wouldn't be too hard taking into account the impact of The Supremacy.