The M16 sucks. On 2 occasions (firefights with the Viet Cong) it did not properly chamber the ammo properly and resulted in jams that put my life in danger.
The A1 version certainly did suck. The A2 version is a much better weapon, and one of the most accurate and ammo versatile platforms there is. Shooting HP competitions, I went from just barely making Master level for years, up to High Master almost overnight when I switched from Supermatch M14s to an AR15.
M14 for the win.
They initially used the wrong powder in the ammunition.
It absolutely did suck at the time. It was a super finicky weapon when first released and Vietnam was about the worst place (maybe outside of a desert environment) where a weapon that finicky could have been deployed. Problems like you mention were extremely common and resulted in some major R&D work to make it better. The A1 was better. The A2 was a huge improvement.
What made the M16 great were decades of fixing all the problems that made it a terrible weapon to start. That and its versatility. You can reconfigure that thing 17 ways to Sunday without much effort.
Jeez, why didn’t you just ask for a time out to clean your weapon?