That is not true, Hornady, Winchester and Copper Creek all load 6.5CM ammo.Yes, you can have a .22-250 re-barreled into any short-action caliber you want, provided it has a standard (.470") bolt face.
If you handload, I would look into the .260 Rem AI, over the 6.5 Creed. The Creed is too proprietized. There's only 1 company making brass, ammo, etc... I wouldn't want a caliber that was THAT dependant on 1 solo company (Hornady). Go with the .260 AI, because Lapua makes .260 Rem brass, and you can find dies and .260 Rem ammo by quite a few manufacturers. It's been around, and it's tried and true.
Just simply my opinion.
That is not true, Hornady, Winchester and Copper Creek all load 6.5CM ammo.
Hornady, Norma and Nosler make 6.5CM brass.
Build the 6.5 creedmoor, no fireforming there. I'm rebarreling to a 6 creedmoor now to replace a 6x47 lapua barrel. Lapua brass was never a concern of mine. I've shot tiny groups with and without it. gun)