It doesn't fit .308 mags. It has its own magazine specification. For example, The X-Bolt has their own 6.5 Creedmoor magazine. It is not a .308 necked down to a 6.5. That would be the .260Rem. The 6.5 Creedmoor is necked down from a .30TC which is a shorter and fatter casing than a .308.
6.5CM works fine in 308 mags...
30TC is a modded 307Win case, which is really a rimmed 308, nothing more.





















































