Just pick the right load - 300 factory for deer, 350 PMC for elk.Other heavier loads are available , or handload. BTW the 300 @ 1800 fps matches the load Winchester introduced 100 years ago !!! From my own experience the 300s work very well on deer .They won't go far and there is little meat damage. A marlin ought to get at least 1 1/2" groups with factory loads. And when people see the big hole ,they ask - what are you using , a cannon ??