Originally Posted by
RPRNY
The 308, as described above, was a bad compromise made during a transition period in weapons and tactics technology. The fact that numerous civilians have fallen for the marketing ploy that 1/2" or less in bolt throw and 5oz of weight savings in their bolt action hunting rifle is somehow meaningful doesn't change that. Not that retaining 30-06 was the answer. 308 was a classic example of the military fighting the last war by trying to get 30-06 power in a smaller cartridge. 30 cal and 2600 + fps is simply too much recoil for a select fire weapon. The overreaction to the 308 mistake was the 5.56 mistake. Perhaps the planners thought the "next war" was going to be with rodents and small dogs. Yes, it's better for a select fire weapon, is cheaper, and weighs less, but its shortcomings are legion, especially when it's being pushed through sub-16" barrels.
A big part of the problem, as Larry notes above, is the desire to use "weapons systems", which require massive compromises to satisfy the logistical requirement for "one cartridge does all". The fact is that a short and medium range "assault" weapon does best with a larger caliber intermediate cartridge - like the 7.62x39 or 8x33, for example. Plenty of punch, not a lot of range. For longer ranges, a full sized cartridge in the 6.5mm - 8mm range makes sense - more reach. But as long as the logisticians and "weapon systems" types demand a single cartridge, there are going to be bad compromises.
A unit in the Afghan mountains should be equipped with individual weapons capable of consistently hitting man-sized targets with over 1000 lbs energy at 500 yards. They also need suppressive fire weapons that can reach out to 1000 yards. Put that same unit into an urban environment and they need compact individual weapons with relatively high rates of fire, but probably have a 100 yard operating environment. That unit will need over-watch from scout/sniper teams with heavy hitting capacity.
There's no easy solution. But dropping the return to 1959 was a good decision.