AS said, you won't go wrong with any of the popular calibres, all have advantages and disadvantages but none are so different as to pretend there will be much of a killing difference.
If you want to claim choice of projectiles then you should be talking 30cal(308,30'06).
If you want to claim more knock down power you are talking about magnums (Short mags, 7mmRM, 3ooWM)
If you claim soft recoil look at your 6mm through to 6.5mm bore(.243, .260, 6.5 Swede)
You just have to decide what is the most important to you.
Now I just have .223 for the small stuff 7mm08 for general and 7mmRM for long range. and a 308 as a back up/ loaner.
but I could get by with just a .308 if need be.
This is just my opinion and I'm sure there will be 30 people telling me how wrong I am
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