The Actual Marine Corps 3-Week Training Course. The marksmanship skills of the Marine Corps rifleman are legendary. In no other service do recruits receive such exacting training with the rifle as do those who undergo Marine Corps training. A Marine enterprise with the rifle is gained from learning the strict fundamentals of marksmanship which are taught along with the along with the discipline to master these concepts. In this four hour program, you will learn the proven techniques taught to marine recruits during their three weeks of intensive marksmanship training.