Everything I've read about the Vietnam issues weren't due to the weapon itself per se... many if not most of the issues were due to misinterpretations of the "self cleaning gas system" evolving into "gun that never needs cleaning".
I also read that a huge issue was when *someone* decided a different gun powder was better than what the manufacturer specified, and so the recipe was changed. The result with the aforementioned "never needs cleaning" FUD was a large number of fouling-related issues and jams.
Put that smack in the middle of the "bigger is better" mindset at the time which built strong resistance to such a profound change and you'll understand why the issues arose.
Now, what I would like to know is how many of those reports from Somalia are true:
- takes multiple hits to knock down the "skinnies"
- doesn't effectively penetrate the mud huts
And what of the Iraq stories we've all probably heard about soldiers having jams during combat - are they all due to poor cleaning habits? Really? Remember that's what allegedly caused that one female soldier (forget her name now) that was all over the news to get captured... gun was jammed and she couldn't fight.