Thanks, but its still not 100% clear to me. You can use many of the same powders to load 308 as the Creedmoor. But I am not discounting your warning about barrel life. I learn something new everyday and thats the way I like it. :)
Some of it might also have to do with general cartridge design. A good example would be the Winchester 30-30 vs the 32 Special. Ballistic-wise they are close. But, the old 32 Special would burn up a barrel in as few as 500 rounds.