Here we go again.
21% more powder doesn't automatically equal 21% greater performance...Anyone who's ever played around with cartridges or wildcats can tell you that. Cartridge design, burn rates, should angle, wall taper, burn column, all of these factor into performance. The .30-06 still does a great job at what it does, but it's just old school, and the design is old school. The whole entire reason we have the .308 Win (7.62x51 NATO) is because the military wanted a .30 caliber cartridge that would produce .30-06 Sprg. performance in a smaller, lighter, more compact package...And the .308 Win did just that. That's why it exists. "New" designed cartridges (like the Ackleys) are just a much better case design. Scientific facts. Does the old still work? Absolutely. But it's not up to par with the "new" designs when it comes down to burn characteristics and performance. If the old school case designs were so extraordinary, why does nobody still use them when they design their new cartridges...?
As for the 6.5CM, I'm pretty sure we all know where I stand on that one, and that I would not put it above the .308 or .30-06...Ever.
Also, I could see this thread getting really fun, really quickly. Can't wait for the festivities!!!