ok, maybe I'm ignorant, or more accurately behind ... (
Were you in a combat unit in Vietnam?
How much live fire training did you get with an M16 before they sent you over there?
Did you get a lot of trigger time with real enemies in sight?
How many jams did you experience that were caused by a fully loaded mag?
Are you aware of the real problems troops had with the M16 in Vietnam?
It wasn't a fully loaded magazine.
The notion that soldiers in combat rarely use the "automatic feature" is patently absurd.
Why do you suppose the basic infantry weapons issued to soldiers of all nations are capable of full auto fire?
How about the AR15? Do you own one? Have you ever owned one? Have you even shot one?
I have owned a number of ARs and put thousands of rounds through them.
The few times my AR jammed was due to a broken extractor, and in a couple of instances, the gas rings were worn and the bolt failed to complete a cycle - it's called a "short cycle".
The only time I experienced a mag feed problem was when the bullet follower jammed, the spring was broken,
or the length of the cartridge (COL) was longer than 2.26 inches, and those were hand loads.
If you asked a soldier, marine, or SEAL if they would take an AR15 into combat, they'd tell you to shove it up your ass.