Your barrel isnt stabilizing the heavy bullets fast enough
As for perfect deer rifle I don't think there is ONE caliber that is perfect for deer
It depends how you are hunting and where... If your hunting where you will be shooting 500 yard you don't want a 30-30 But if you are hunting thick bush where you wont get a shot over 150 yards you don't want to be carrying a big 30-06 around
This is why everybody needs MANY guns