For (hunting) guns, you will shoot it more working up loads than you will for many years to follow.
Buy a 308 to practice with and save the barrel burner for hunting and a few rounds each year to
confirm zero. Consider this also, while the 6.5 cartridges are very good, 3000 fps with a 160+ gr bullet
is still better than with a 140 gr bullet for hunting. And a 7mm rem mag would give you that without
being the barrel burner the hot 6.5s would be. It would also give you more options to use both lighter and
heavier bullets up to 190 grains. Use at minimum a 26" barrel for best results. A 28" would offer the option
of later rechambering to a larger 7mm cartridge should you desire more horsepower.