It offends many, as truth always does, but the Emperor really is naked.

The 6.5 credmoor is going to take hold because it gives very old, very tried and very true ballistics in new guns. The olderones would not take the longer 6.5 Swede or 6.5 X57 Mauser. But what makes it great is not new ballistics. We have had those ballistics for over 100 years. And much faster speeds since I was about 2 years old (and I am an old man)
The reason the 6,5CM is going to catch on and hold on is the fact that the old 6.5 cartridges did so well and the CM is copying their performance, but the rounds fit in detachable magazines.

Salesmen will jump on this and millions will drink cool-aid by the 55 gallon drum. It's worked on many shells that don't have much merit,,, and it also works on those that do (like the 6.5CM)

But the Merit the CM has is a combination of gun and shell, not shell alone.

If I were using a 6.5 MM for long range work in a standard bolt action I would not build or buy a 6.5 CM. I'd make a 5.6 Swede. Or even a 260 Remington (for the cheaper brass I can make from 7.62-NATO)

Those that see their favorite shell as a god will worship it, and be offended at those that don't. So be it. They are as entitled to their belief as anyone.

But in all history belief never changed a fact, or the truth, no mater how "hard' someone wants to believe it.

Here are FACTS.
6.5 CM with a 26 inch barrel operating at top SAMMI pressures as listed in the 2016 SAMMI spec sheet.

129 GR bullet with a G1 BC of .485 Top velocity of 2910 FPS,

Same bullet with a 260 Remingtom, using the same action with the same barrel length, at the same pressure. 2980 FPS (70 FPS faster)

Same bullet with a 6.5X55, using the same action with the same barrel length, at the same pressure.
3020 FPS (110 fps faster)

Same bullet with a 6.5-06, using the same action with the same barrel length, at the same pressure.
3048 FPS (138 FPS faster)

Now, just for fun, we'll look at the long heavy load for the 6.5CM. Using the same test gun at the same pressure, but using a match 143 grain bullet. G1 BC of .625 Muzzle velocity is 2789 FPS. Outstanding long range flight characteristics!

Here is a set of ballistics to look at.
BC of .525 ( inferior to the above BC by .01) 150 grain bullet. (7 grains heavier than the bullet above) Same action. 25" barrel (1 " shorter) Loaded to top SAMMI pressure as listed in 1968 Spec sheet.
3009 FPS (220 feet per second faster then the best of the 6.5 CM loads

So the .01 superiority of the .625 BC, VS a BC of .525, is offset by the 220 FPS faster velocity of this load, and the point of equality in trajectory is WAY out there. I would guess about 750 to 800 yards, but I don't have the chart to look it up.

Now both guns will have to have their muzzles elevated to hit a deer at that long range, so both have to be held up. Right?
If you can hold still enough to hit, holding a bit lower or a bit higher is not relevant to the a hunter. Bullet construction will matter at that range, but a .01 BC advantage or disadvantage is not an issue. That's a set of mathematical calculations but it's the man that must do the holding and the shooting. If you can hold X inches high you can hold Y inches high. If you can't hold, don't fire.

Is the last load "better"?

Maybe ,maybe not.

Personally I don't think so. But it's not worse either. It is more powerful, but does that make it better?

Is a good pick-up better than a good sports car?
Yes and no.
Depends on what you want to do with the auto.

The above information is not a format of worship. It's just a set of mathematical facts.
And fact by themselves don't lead to truth unless we want to know truth. Truth never makes any difference until there is enough humility to want to know it, even if you don't like it.

That's why arguing with "liberals" is fruitless. They hate facts. They hate the truth even more. They won't listen, their minds are already made up.

If your mind is made up and you are looking for facts to "prove" your religion, no amount of truth will move you.

Facts are just facts. If we stop worshiping things we'll start to think more clearly and not be offended if someone else drives a different type of auto, or shoots a different gun.