Advantages of a smaller caliber

[Cossack]

Mostly weight and recoil. For use out to say 250 yards the smaller calibers like 275 Robers, 25/06, 260 and 7/08 are just the ticket for deer. The 243 is on the light side for our large northern deer. It works but there is less margin of error. Especially important in crowded hunting conditions where the deer could travel after being hit.
My Kimber Montana weighs just 6.5 lbs trailside. Loaded to 2900 fps with a Barnes TSX 140 grain it's about as near perfect as my use - stand and still hunting - calls for.