The 6.5 Creedmoor is preferred when one wants to use long and heavy bullets in a standard .308-length magazine. The shorter case leaves more room for the long noses.
Further, stock 6.5 Creedmoor rifles come standard with the faster twists needed to stabilize these long bullets.
Regarding Elk and the 6.5, the 6.5x55 Swede is probably the world's most prolific elk harvester, thanks in part to the 160 gr lead core and 140 gr lead free bullets in the cartridge. The Creedmoor will do better.
Further, stock 6.5 Creedmoor rifles come standard with the faster twists needed to stabilize these long bullets.
Regarding Elk and the 6.5, the 6.5x55 Swede is probably the world's most prolific elk harvester, thanks in part to the 160 gr lead core and 140 gr lead free bullets in the cartridge. The Creedmoor will do better.