The Mozambique Drill, also known as the Failure to Stop Drill, or Failure Drill, is a close-quarter shooting technique in which the shooter fires twice into the torso of a target (known as a double tap to the center of mass), momentarily assesses the hits, then follows them up with a carefully aimed shot to the head of the target. The third shot should be aimed to destroy the brain or brain stem, killing the target and preventing the target from retaliating.
It is important to note that in the heat of such an encounter, all but the most well-trained shooters will be unlikely to score such a precise head-shot. For the vast majority of people the point of aim should remain the torso.
Rhodesian Mike Rousseau was serving as a mercenary in the Mozambican War of Independence. While engaged in fighting at the airport of Lourenço Marques (modern-day Maputo), Rousseau was armed with only a Browning HP35 pistol. As he turned a corner, he bumped into a FRELIMO guerrilla armed with an AK-47. Rousseau immediately performed a "double tap" maneuver, a controlled shooting technique in which the shooter makes two quick shots at the target's torso. Rousseau hit the target on either side of the sternum, usually enough to incapacitate or kill a target outright. Seeing that the guerrilla was still advancing, Rosseau made an attempt at a head shot that hit the guerrilla through the base of his neck, severing the spinal cord.
Rousseau later related the story to an acquaintance, shootist Jeff Cooper. Cooper later incorporated the "triple tap" maneuver (two quick shots to the torso and one quick-aimed shot to the head) into his practical shooting technique. Rousseau was later killed in action in the Rhodesian War.