School of the American Rifle - AR-15 Bolt Carrier and Rifle Cut-Away Video Demonstration
Jeff Gillis found what is possibly the best and most complete training video regarding the AR-15 platform. It is approximately 21 minutes in length and will give you the most complete understanding possible on what happens when you squeeze the trigger of your black rifle.
I was issued my first M-16 in November of 1968 and given the most rudimentary instruction on how it functioned. If I'd had this video back then I would have been a much more effective 'grunt'.
Click here to watch the entire video on YouTube: https://youtu.be/Uv6a1hs9U5o