Now you tell me - 260 Rem. Haha.A 260 Rem will let you use your 308 brass. I confess, I have a Grendel, 260, Creed, and 6.5-06. I have a couple of 308s, too. As I move to 75 in 3 months, recoil is an issue with a twice repaired spine. The 260 is a peach with 140s at 2700 in 22".
???Look at the 308 Bellm cartridge