Dead Aim (D20 Modern Feat)
From D&D Wiki
You are capable of lining up deadly shots with ranged weapons.
Prerequisite: Wis 13+, Far Shot.
Benefit: Before making a ranged attack, you may take a full-round action to line up your shot. This grants you a +2 circumstance bonus on your next attack roll. Once you begin aiming, you can’t move, even to take a 5-foot step, until after you make your next attack, or the benefit of the feat is lost. Also, if your concentration is disrupted or you are attacked before your next action, you lose the benefit of aiming.