well to me the biggest part of the decision is personal preference, and to make sure you make a good shot... as I said, that is my own opinion, and how i feel.. but a good for instance : A freind of mine just took his son out for youth weekend and he got his first spike buck, he was using a .223 would I ? no.. but that is me... his father uses the same .223 every year it is what he likes to hunt with, that is his decision and tat is fine, I like a .270 or bigger (right now I am using a mossberg 500 12 ga. and rifled slugs due to the fact that my .270 was borrowed by a so called friend , and never returned... next thing you know he moved out of state , and i am out my investment on a damn fine gun and scope) but at least i was able to pick up my shotgun for cheap until i can reinvest) back on subject... not everyone will agree on caliber, and that is fine. just concentrate on shooting inside your range, ande making a good clean shot other then that shoot what you are comefortable with.
ANYONE WHO TELLS YOU HUNTING IS WRONG... TELL THEM TO READ THE BIBLE:
Now then get your weapons-
Your quiver and your bow-
And go out to the open country-
to hunt some wild game for me