It is becoming an old arguement, but I agree 223 is light for deer, or atleast restricting. Lung and heart shot almost anything will work. Not sure why a healthy adult would choose 6mm for deer, unless you could only own one gun. Most of I suspect have more than one. You can load 30-06 to 110 grain, if you can only afford one gun.
I like what Elmer Keith said, I want my hunting done when I pull the trigger.
