My buddy Keith still has and loves his 6.5x68S.(& 8x68S)

He was using a 6.5x68S back in 1979 when I met him(at work)& he still hunts with one today, albeit with a new(er) barrel.

I chambered up one on a new-barrel 6.5x55 M96 back in the late 80's.
i didn't run it to the nuts, but still ran 129gr. Hornadys at 3,100fps.
Keith was pushing those at 3,300fps in his 6.5x68.
To extract a loaded round, I had to partially pull the bolt. I think Kieth was using 4 or 5 grains more H870 than I was using.
That is a hell of a good round. The only .264 Win. Mag I ever had, was a M70A, post 64 that had a ridiculous 22" bl. My .260CLC wildcat(basically 6.5x57IMP) ran less than 50fps slower(26")with a 120gr. Barnes XLC), but did that with 20gr. less powder than the .264. 3,308 fps vs. 3,350fps.