When you compare an 18" 6.5 to an 18" 308 you may still like the 6.5. The factory loaded 6.5 140s go exactly 2550 fps from the 18" with a G1 of over .6. Most factory loaded 308s with "long range" bullets are going to be in the high 2400s maybe 2500 and only a have a G1 BC around .5.

I like the higher BC so that I can use a shorter rifle and have the same or less wind effect compared to 30 cal.

I have been shooting an 18" 6.5 Creed with full-time suppressor for a few years now. I am very impressed with it out to 800 yards. I have been behind that short rifle when some large game has fallen to the ELD-X. Personally, I cannot go back to a longer barrel.