If you really want to shoot out to 600 yards then you need at a minimum a powerful 30 caliber or larger. You will also need a good quality factory rifle-Then you will have to take it to a gunsmith for some custom work. You will also need a high quality scope with a first class mounting system. You will also need to start reloading to customize your ammo. IMO you are looking at a minimum investment of around $3,000(and that is the low end)to be able to be consistent enough at 600 yards to ethically shoot at a game animal. Tom.