Learning this method can be advantageous for big game hunters – especially if there is no time to calculate all of the variables needed to adjust the scope. As I lay prone on the ground, squinting at the target only 100 meters away, the training instructor began shouting orders. I was a young airman basic in the United States Air Force and, unlike other branches of the US military, we only got to spend one day at the firing range. Using an M-16 shooting 5.56 NATO ball ammo, we were told to aim for “center mass.” The target was...