Retronaut has published a scan of the Army M16A1 Maintenance Comic from 1968.
It is a wonder they found time to fight the Vietnam war between all that cleaning. I wonder how many of the M16A1 problems were caused by over cleaning and how many bores were ruined by cleaning rods. I commented to a friend that this shows how far the AR platform has come, he replied is also says just as much about how much we have learnt about the platform.
[ Many thanks to Whaleoil, Christopher & for emailing us the link. ]