Actually its EXACTLY the reason I am such a 6.5x55 fan. And no, those are not mutually exclusive.
While I have not experimented with 260, I have gave an honest go to a 6.5CM with Savage MSR10 LR. I would imagine I could have gotten beyond 2300 rounds before needing a replacement if I shot it as a bolt-action rifle vs rapid strings- I was not impressed. Also, creedmoor must be a carbon magnet, because I literally have spend hundreds of dollars just trying to find the most effective way of battling carbon fauling/carbon ring...
Sounds as Noreen rebarrel would be a way to go.
P.S.
6.5CM is fun and accurate round, out to 800m I have shot two quality rifles in 6.5x55 and 6.5CM and I have to say that accuracy is the same, in my opinion. Now, considering my reloading equipment and components stock - I am considerably better equipped for 6.5x55 - so another consideration. With that said- I did get a better case life out of Lapua Creedmoor cases, although cleaning it was a bigger pain on the ass.