Another good 6.5 for 139's-142's is the 6.5x300Weatherby Mag.. You could drive the 142's around 3500fps without a problem.. Great Long Range gun!!!

I wouldn't be quick to toss the idea of the basic 6.5x55. All the available reload data is very low pressure. On a strong action, you can load the Swede to 3050 fps with a 120 grain bullet, and even 3125 fps is possible, depending on how close to the limit you want to be. Just the basic cartridge, with modern loads, is a heck of a performer.