NAVMC 2550 governs marksmanship principles and techniques for precise aiming, trigger squeeze, positions, and rapid fire.
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It covers sight alinement and sight picture, trigger squeeze, standing, sitting, kneeling, and prone positions, and follow through. It also addresses the sling, scorebook, rapid fire, sight adjustments, true zero, wind direction, and wind velocity.
SIGHT ALINEMENT consists of focusing the eye on the frontsight blade and centering the top of the blade in the peep sight. (paragraph 5)
The most important single factor in marksmanship is the trigger squeeze. (paragraph 2)
Try to squeeze off your shots within 5 or 6 seconds. A longer period will tire your muscles. (paragraph 1)
"The sight setting necessary to hit the center of the bull on a day when no wind is blowing." (paragraph 9)
One click of elevation or deflection will move the strike of the bullet one inch for each 100 yards of range. (paragraph 8)