The 25 caliber bullets are a little on the light side to begin with so I would lean towards the heaviest bullet to give you good penetration. Even the 117-120 grain bullet gives you plenty of speed out of a 25-06. 2990 for factory and well over 3000 with handloads. There is nothing gained by sending an 85 grain bullet out at 3200 fps. Unless you're shooting pronghorn nannies at 500 yards .