Re: 6.5 Creedmore VS 6.5x284
I currently have a rifle in both offerings. I built the 6.5/284 first. It was meant to be a Pronghorn, tactical, long range rig. I'd say it came out pretty good, but is on the heavy side for carrying - 16 pounds. So, I decided to build another lighter model for carrying and deer hunting. I decided to go with the Creedmoor. I will tell you the components used on both and what I like/dislike about both.
6.5/284: 700 Long action, McM A2, Brux Sendero, 26", 16 pound with optics, 140 Bergers, Lapua brass.
Shoots lights out, under .5 moa. Pinging the 1000 yard target at will, Lapua brass seems still available. 2950 fps. It's heavy and with my can is almost cumbersome in some situations (couldn't get swung around fast enough last year on a nice buck)
6.5 Creedmoor: 700 short action, McM A3 sporter, Brux #5 fluted 24", 12 pounds with optics, currently shooting factory 140 loads. About .7 moa(need to work up a load) I have all the brass to load just haven't yet. Brass seems available. 2670 fps.
Here's my take: both shoot really well. I think I can get the same accuracy out of the creedmoor with a little work. They are honestly just set up for different things, but you could reverse them and get the same results. I love both cartridges and you could go with either one and not be wrong.