“Recently, Springfield introduced the iconic M1A rifle in 6.5 Creedmoor. This got my attention. The AR rifle has sucked the life from most other self-loading rifles but not the M1A. This is a big step. Perhaps, I should look harder at the two cartridges—6.5 and .308 for brevity.
The 6.5 Creedmoor is similar enough to the .308 that re-chambering a popular rifle isn’t a problem for the major makers. The Creedmoor uses a skinny light bullet to achieve good ballistics. This isn’t necessarily a higher velocity loading, but instead, it is a very efficient loading. The 6.5 is a popular long-range number that has seen much use the past decade or so for firing beyond 500 yards. And that’s the deal right there—long range.
The .308 is a great go-anywhere do-anything cartridge but it isn’t the finest long-range cartridge. Long range results with the .308 hinge on a great rifle and optics, and also a great shooter. At ranges up to 500 yards—with proper load selection—I don’t see that much difference, except perhaps in wind resistance. At 1,000 yards you see the 6.5 has a big advantage in hitting the target easily with less calculations.”
Read more @
http://blog.cheaperthandirt.com/review-6-5-creedmoor-308-winchester/