Hint - Destroying Sam Sites Easily:

The easiest, most effective way of destroying Sam (Surface-To-Air) Missiles in the game, is to simply aim from a distance using any sniper rifle (Foley) is the man for the job, mostly. A single or double tap on the 'red' area of the missile will result in a Boom! The beauty of this method is, you are out of harms way and it is again a stealthy approach.