Unfortunately, there are more than a dozen cartridges in 6mm that have held dominance in the market at different times. You will need to determine the specific cartridge your rifle is chambered for. The Creedmoor is a relatively new cartridge though.
6mm Remington (earlier cartridge) and 6.5 Creedmoor are two totally different cartridges. Google it... do your homework. Say safe and don't blow up your rifle or worse, your face! I have a 1980 beautiful Remington 700BLD chambered in 6mm Remington and I love it... hard to find ammo though. And when I do, it's difficult to afford. One of the reasons I reload my own rounds... along with 32 Winchester special (try to find those) same casings as 30/30 Winchester, just have to expand the casings a tiny bit... Just be careful to keep them seperate from your 30/30's and mark them clearly as such.