|關於an overview of assault rifle models in all games，參見assault rifle。|
The Fallout 3 basic Assault Rifle is the R91.
R91突击步枪是一把适用范围很广的全自动武器，在中近距离十分有效。不过，由于并不十分高的精度和相对较低的单发伤害，它很难对远距离的目标实现有效杀伤，在面对重防护目标（例如辐射巨蝎）时的效果也不十分理想。虽然有着这样那样的不足，但对于喜爱小型枪械的玩家而言，它会是前中期值得拥有的武器。Condition degrades at a moderate rate. Poor-condition assault rifles are sold by many vendors across the Wasteland, and are often found in raider camps, buildings, and Metro tunnels.
The basic Assault Rifle differs from the Chinese Assault Rifle: the latter does more damage (44 DPS compared to the R91 Assault Rifle's 32 DPS), is more durable, but is also scarce. Spread and magazine capacity is identical.
Ammunition is relatively abundant. See 5.56mm page.
- Infiltrator (The Pitt add-on) - A scoped, silenced version of the R91, it functions similarly to the Silenced 10mm Pistol in that, while not as loud, it deals less damage than its roaring cousin.
- Perforator (The Pitt add-on) - A unique version of the rare Infiltrator, it has the slowest rate of fire of any assault weapon.
- Wanda - A unique R91 that was cut from the final game.
This rifle was standard issue for the US Army and National Guard during the urban pacification operations and combat. Fortunately for our purposes, the National Guard had been fully deployed around the DC area during the time of the war. As a result, the R91 is readily available for those willing to search. Although nearly two centuries of scavenging has reduced the numbers of working units, the R91 remains a favorite of Slavers, Raiders and Mercenaries. This rifle can often be obtained from legitimate traders and arms dealers.
Like any firearm, the R91's effectiveness and accuracy can suffer without regular maintenance.
- In Fallout 3, this weapon is called simply "Assault Rifle". However, this article's title uses its full name to distinguish it from the AK-112 Assault Rifle from Fallout and Fallout 2. The rifle is almost an exact visual duplicate of the Spanish CETME Modelo C. but chambered for 5.56mm.
- This weapon, along with the Chinese Assault rifle, appears in the Operation: Anchorage combat simulator, with a pristine look as opposed to the Wasteland's weathered and beaten finish.
- There are some locations in which 4-7 Assault Rifles can be found, all in (very) bad condition:
- The National Guard Armory.
- The National Guard Training Wing.
- The Fort Constantine bomb storage inside a very hard locked door.
- The Assault Rifle can clip through targets or level geometry in V.A.T.S. This results in all shots missing or being absorbed by geometry, even when the muzzle protrudes past the obstruction. Against point-blank targets in V.A.T.S., the rifle sometimes inflicts minimal damage. (confirmed all platforms)