Actually, I think .308 and 30-06 are essentially the same round. The 30-06 was developed from the 45-70 of which the gummint had plenty o brass around at the time so it made sense to use it and the slower burning powders of the day needed the space. More modern powders (50 yr ago) burned faster and took less space to develop the same pressure so the .308 Win was developed to take advantage of that "empty space" that is in most 30-06 nowadays. At least that is what I understand happened. Look at the ballistics, they are the same bullet at about the same muzzle vel.
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You are essentially correct on your assessment of the two rounds, as they were originally developed the .308 developed 2860 fps(I am pretty sure, might want to check that) and the 30-06 developed 2970 fps, both using a 150 grn bullet. The velocity differential remained about the same with other weight bullets. The .308 was simply a short version of the 06 round and developed the same pressures in a shorter case. New powders have make both considerably more powerful today.
I prefer the 06, simply because I grew up with it, took my basic training with it, switched to the .308 when the M14(great gun BTW)came out and got out of the Army before the M16 came along.
I know the 06 round, I load for it and can do it in my sleep if I have to and never saw the need to go to the .308, but it is superior in the fact it uses less brass, less weight, to get the same job done
I was always puzzled why they developed it however, when they had the .300 savage round waiting there just screaming to be used in a modern day assault rifle. I guess wanting to keep a full power load won out on that one.