A key to any military operation is the deployment of firepower against an enemy force to deny the enemy the ability to place accurate fires on your force. From a paintball event to a tactical operation the goal is always to force your opponent to take cover so they cannot engage you. Suppressive fire, also called covering fire, is the term used to describe area denial fire that degrades the performance of an enemy force below the level needed to fulfill their mission. In most situations the intended effect of suppressive fire is mostly "psychological" rather than destroying the enemy. Receiving well aimed fire from a high powered rifle will make any one feel unable to safely perform actions other than seeking cover. Suppressive fire is most often described as "shoot to keep their heads down" or "shoot to keep them pinned down." Most groups employ AR-10s (7.62/.308win) as their primary system for support elements. AR-10s are capable of providing a high rate of precision fire and able to defeat light skinned vehicles and fixed positions. Any .30 caliber system such as a M1A/M14 or a M1 Garand performs well as a suppressive fire system. A final consideration for suppressive fire is the discipline to support a sustained rate of fire over a period of time. Support elements must not fire all of their ammunition before the mission is complete. It is extremely easy to get carried away during an engagement and fire all of your ammunition. Throughout history many attacks failed because a support elements inability to sustain suppressive fire throughout the operation, allowing the enemy to react and defeat an attacking force.