I'm not going to win any popularity contests with my next remark. The M14 was obsolete before it got off the drawing board. Not my personal opinion, but that of a lot military leaders, gun designers, and one of my firearms repair instructors. Most say that it was a refined version of the M1 and nothing more.
That would be the same M1 that Patton described as the best battle implement ever invented?
Yes, the M-14 is a refined M1 Garand, but if it were obsolete, why WTSHTF in various endeavors after Grenada do our people continue to flock to the M-14 for its stopping power and it's long range capabilities - far longer than the AKs and ARs. It's not plastic and aluminum, and it certainly may not the best for urban warfare for its length. But it is still an excellent weapon, and hardly obsolete.
Besides, when we dumbed down the military, moving to a spray and pray weaponry (what was the shot-kill ration in Nam - 2 million shots for 1 kill?) - easier than making them riflemen - I hardly think that obsoletes previous generations of weapons, just makes them different.
It is heavy though . . .