User blog comment:CoD addict/Shooting off hats/@comment-2130641-20100704112408

It is obviously easier on npc's with big hats (Walton's Gang or Banditos).

Try this as a first shot, when doing a gang hideout (ie:Twin Rocks, Tesoro Azul), when ennemies are not aware yet of you. Without DeadEye, as DeadEye level 2 (as you said) will result in a headshot. Then aim for the border of the hat.