I was fortunate to have received my first marksmanship instruction in Boy Scouts in 1964. Our Scoutmaster taught it the way he'd been taught M1 rifle marksmanship, which was really a recycling of the old M1903 POI. That was back when the loop sling, hasty sling, and sitting position were still taught. The Army gave us weekly access to a 50-foot indoor range at Fort Belvoir and it also lent us a half-dozen Springfield .22-caliber rifles, either M1922A1 or M2, with Lyman rear peep sights. My Army marksmanship instruction in 1977 consisted of a 50-minute lecture on the "Eight Steady Hold Factors" before we zeroed. I believe the abbreviated approach was mainly to save time.