As gun ownership among young Americans drops and the Army trains a new generation more accustomed to blasting out emojis on cellphones than taking aim at targets, drill sergeants are confronting a challenge: More than half of raw recruits have never held, let alone fired, a weapon.

A study of U.S. gun ownership reports teens and 20-somethings — who form the bulk of the Army's rookie soldiers — don't have nearly the exposure to guns as past generations.

So the drill sergeants tasked with transforming recruits into marksmen are adjusting their approach, adopting a more mentor-like approach while barking out fewer orders. At the largest basic combat training post — in South Carolina — they regularly offer guidance in measured tones as soldiers fire M-4s at distant targets.