my 6,5-284 Norma had 1-8,5 and worked well with 140-155 grain bullets and I would not choose a barrel shorter than 26 inches - might as well have a 6,5x55 and burn less powder.

My next 6,5 will be a 6,5X64 Brenneke, simple to get brass for and no feeding problems. My old 6,5X64 Brenneke was phenomenal, it was "best" with 140-155 grain bullets and 1-8 in twist.