The movie Sniper is actually a factual story loosely based on the biography of a United States Marine Corp Sgt. Carlos Hathcock. Sgt. Hathcock was a sniper during the Vietnam war. A book called "Marine Sniper" written by Charles Henderson has the same stories where Tom Beringer crawls across the field to get into range to shoot the drug lord and also where Berenger is stalked by the enemy sniper where he shoots him the other sniper and the bullet goes through the rifle scope. Those two scenes actually happened in real life.