Why The 6.5?
The 6.5 Creedmoor cartridge was designed by Hornady ballistics engineers in 2007. The concept was to develop a highly efficient 6.5mm cartridge that would rival the .260 Remington in powder capacity but better accommodate long bullets in a short-action rifle. To accomplish that, they based the 6.5 Creedmoor cartridge on the .30 Thompson/Center cartridge rather than the .308 Winchester case. Initially, the 6.5 Creedmoor’s ballistics don’t look like those of a long-distance cartridge. For the 140-grain Federal American Eagle Open-Tip Match (OTM) round, the advertised muzzle velocity is 2,700 fps compared to 2,600 fps for a .308 Winchester with a 180-grain bullet.
The key to the 6.5 Creedmoor’s success at long-distance shooting is its high ballistic coefficient (BC), especially when using Hornady’s new 143-grain ELD-X bullet. The ELD-X has an extremely high G1 BC of 0.624. I’ve seen a custom 6.5 Creedmoor rifle with a 12X scope use this ammo to engage targets to 1,200 yards. At that distance, the ELD-X is 488 inches low while the 180-grain .308 Winchester is 639 inches low—a difference of 151 inches in trajectory for bullets that only started with a difference of 100 fps in muzzle velocity.
The 6.5 Creedmoor also beats the .308 Winchester handily at long-range terminal ballistics. At 500 yards, the Creedmoor retains more bullet energy than the .308, even though the .308 delivered almost 300 more foot-pounds of energy (fpe) at the muzzle.