How to Build an AR-15 Upper Receiver Presented by Larry Potterfield of MidwayUSA

That darn little dust cover pin C clip!

CW3 Kevin Storm thanks for the share, of the most informative.

The tools look like they would cost as much as the rifle. I would love to do a build like that at some point but time, the right tools, a crap pot full of patience and other activities keep me from it so I will buy them fully assembled by someone else with the tools, inclination and time to do so.