MW2 Killstreaks Guide PART 2 COUNTER-UAV, SENTRY GUN, PRECISION AIRSTRIKE
Description: Scrambles the enemy radar for a short period of time, even if they don't have a UAV in the air.
Counter-UAVs fly around the map, so they can be shot down just like regular UAVs.
Description: Airdrop a placeable XM312 Sentry Gun. A helicopter will drop the weapon, which you can pick up and place anywhere you want. The Sentry Gun (box) can be stolen by anyone, just like the Care Package, so be sure to pick it up straight away. You can move the Sentry Gun around even after you've deployed it, but it won't fire until it's placed.
The Sentry Gun has a 180 degree turn on its turret and can pitch up and down, but it can't detect players using the Cold-Blooded perk. They are most effective when placed in high places.
Sentry Guns can be temporarily disabled with Flashbangs and Stun Grenades. Normal weapons don't do much damage to it, so use explosives instead. You can instantly destroy them with a melee hit or a Throwing Knife - silly, but true. The turret can over-heat if it's fired for too long, so use that to your advantage. The Sentry Gun will disable itself after 90 seconds.
Description: This is much like the Airstrike from Call of Duty 4, but this time you can control the direction of the Airstrike for more accurate kills.