I shoot the 140 Bergers out of my 6.5-06AI that I built a couple years back. I've killed a bear, an elk, and a bunch of deer with it at ranges of 80 yds to 450 yds.
Id shoot the hell out of it then rebarrel when the time comes. Never had a 264 but have always been impressed with it. If a pre 64 mod 70 walked into my life would snatch it up as spent several years looking for one back in the mid 80's. BTW nice looking rifle to the op