As noted a larger caliber might be better for 600. BUT I've shot 223 with heavy bullets and iron sights at 600 to 1000 for so long now (in an AR to boot) that I know its very possible. I've seen out state championships at 1000 won with that 223 and 80s. I've seen it won with 223 and 90s. So its workable. Long barrel life, cheap to shoot. Take the savage and replace the barrel with a fast twist and you are ready to roll.
My personal thoughts are that if I'm gonna go bigger, go to a 6.5x284 or 7mm wsm
right away. The in betweens don't impress me much. Though the 6.5 Grendel with a long barrel should be awful tough as an in between round.