From Lexicanum

The Ranger Long Rifle is the Eldar equivalent to the Imperial Sniper rifle. It is complemented with a number of highly effective scopes and sights which allow the attacker to find any weakness in armour and exploit it to the full. They are carried by Rangers and Pathfinders when they leave their Craftworlds and explore the galaxy as it fits best with their stealthy approach to warfare. Eldar Long Rifles make use of gravitic accelerators, which remove all recoil from the weapon, and render it almost completely silent in operation.

Sources

• Warhammer 40,000: Wargear
• Tales from the Dark Millennium (Anthology)

See also

• Eldar Weaponry