This is my second response to this thread. I think the immense popularity of the Crudmoor is a fad thing. It's probably here to stay and I can see it is a very useful round, I just doubt it's really better than some older cartridges. I think a lot of its popularity is largely due to market hype. It answered one particular question or rather resolved one issue. It allows bullets to be seated out farther than does a .260 Remington and that only in a short action like the Remington 700 Short Action. If you build one on an intermediate or long action you can get more performance out of the .260. Does it really have that many more bullet choices? And how many different bullets do you need? This was one argument against the .270 up until a few years back. Now there's plenty of bullets available for it. Also, the 7mm-08 has as many I believe. And as I said, How many bullets do you need? Even back in the 80s and 90s I hunted with the .270 and only needed a couple of weights. Sometimes I think that bullet availability argument is over blown for argument sake.
The popularity of the 6.5 Creedmoor is long past the “fad” stage.
The 6.5CM solved more than one issue. As you point out, it allows bullets to be seated further out. Equally, and actually more important IMHO, the tight chamber and ammo specs and fast 1-8 twist created a combo that shoots very well with factory ammo and heavy-for-caliber bullets with reduced recoil. Lower pressure also extends barrel life. It is an outstanding target round that does very well in the field as well. If you have a 6.5CM there is very little reason to get a 7mm-08 for hunting, whether you handload or not.
Although similar bullet types are available for both cartridges, there are far more factory options for the 6.5CM (83 vs. 30 at midwayusa.com). Same thing with rifle options – there are far more for the 6.5CM, especially in configurations for long range shooting. What I found on a quick 6.5CM vs. 7mm-08 search was 23 to 6 7mm-08 for Ruger, 57 to 30 for Savage, and similar ratios for Kimber and Tikka.
For someone that handloads or decides to buy a custom rifle, factory configuration, twist rates and chamber spec options are far less of a concern. They represent a very tiny fraction of total buyers.
For a multipurpose target/varmint/big game rifle, the 6.5CM is the easy choice. For varmint bullets the 6.5 offers 95g V-MAX bullets with a B.C. of .365 and you can push them to 3371fps per Hogdgon. To get that high a BC in a 7mm varmint bullet you need to go to 120g V-MAX and you only get to around 3200fps. The 7mm-08 needs more powder and a heavier bullet, has more recoil as a result, and falls short ballistically.
For big game hunting the story is much the same. To get the same .625 B.C value of a 143g 6.5mm ELD-X you have to go to a 162g 7mm ELD-X. Again you will burn more powder for lower velocity. The 162g might be a better choice for large deer or elk and up, but for most purposes 6.5 will get the job done just as well. When it comes to the 175g 7mm bullets, you lose even more velocity and have much lower B.C values for bullets suitable for the 7mm-08 standard 1-9.25 twist rate. For the high B.C 175g bullets a 1-8.5 twist or faster is recommended. Finding a 1-8.5 twist 7mm-08 limits factory options.
Both are fine cartridges. If you have one you have little need for the other. For those with neither, the 6.5CM makes the most sense most of the time.
