more scope for error with a bigger heavier calibre they can both kill and both injure but you need to be more precise with a smaller one otherwise whats the point of different calibres for fox, deer, boar
sorry but that is not true shot placement is more important for instant dispatch the bigger calibre does not have more scope for error i have shot roe deer just over 200yds with my .308 150grn sp and the exit hole was about 2inch heart shot, this was on flat open land the point of a bigger cal is you can use a lighter or heavier bullit head weight instead of haveing a couple of rifle