Sniper

Sniper is a perk in Fallout, Fallout 2, Fallout 3 and Fallout Tactics: Brotherhood of Steel.

Fallout, Fallout 2 and Fallout Tactics

 * Requirements: Level 18 (Fallout), 24 (Fallout 2, Fallout Tactics), Perception 8, Agility 8, Small Guns 80%
 * Ranks: 1
 * Benefit: You have mastered the firearm as a source of pain. With this Perk, any successful hit in combat with a ranged weapon will be upgraded to a critical hit if you also make a Luck roll. It adds another luck roll of (10*Luck). 10 LK means every hit is automatically a critical hit.

Fallout 3

 * Requirements: Level 12, Perception 6, Agility 6
 * Ranks: 1
 * Benefit: With the Sniper perk, your chance to hit an opponent’s head in V.A.T.S. is significantly increased.

Not a bad investment if you use projectile weapons. Nearly every creature takes more damage from headshots, and more headshots mean less ammo used. Remember that there is a perception point available from a quest reward if you don't want to spend the points at character creation.