The Automatic Rifle is a powerful support weapon firing .308 Rounds. The weapon holds 20 rounds in a box magazine, has a higher base damage per shot than any other fully-automatic projectile weapon and a comparatively high Critical Chance.
Although it is a rifle with a very long barrel and high-powered rifle ammunition, it suffers from poor Weapon Spread when compared to bolt-action and semi-automatic rifles, having the highest spread of any fully-automatic weapon in the game. Even when upgraded, it has the lowest fire rate of any automatic weapon, and its low durability means it will degrade rapidly with frequent use and require regular maintenance. The Automatic Rifle fires two round bursts with each separate attack in V.A.T.S. at the cost of 35 Action Points.
Villa Police Station - one can be found to the left of the main entrance through the locked contraband storeroom door, along with boxes of .308 Rounds. The contraband room cannot be picked and can be only accessed via a computer terminal on a desk next to the door with a Scienceskill of 75 required.
Villa - can be found next to one of Dean's Secret Stashes on a rooftop, in a courtyard covered with the Cloud. Another can be found in a Footlocker inside a courtyard a short distance northwest of the doors to the Residential District, behind the northwest pillar.
Sierra Madre Casino - one can be found across from a gun cabinet on the second floor. Another can be found in a gun cabinet in the cashier's office on the first floor.
Salida del Sol Courtyard - next to a corpse and a Dean's Secret Stash, in the water with all the Sierra Madre Chips.
Salida del Sol South - one in a gun cabinet on the ground floor of a building south of the building with the upturned pool table. Another can be found east of the Salida Switching Station, on a second-floor balcony next to a beeping radio.
↑Question: "Is the Automatic Rifle from the Dead Money add-on based off of the M1917 Browning machine gun?" Sawyer: "No, it's based off of the M1918 but with modifications to the grip and other parts." JESawyer on Formspring (Archived)