I wouldn't hunt deer with any of the 22 caliber bullets like .222, .223 or 22-250. Most are somewhere in the 55 to 60 grain weight range and those little bullets moving that fast can just blow up on impact and not penetrate enough to get the job done. And most of the time they are not going to exit the far side of a deer which can leave you with a scant blood trail on any deer that doesn't drop in his tracks. Can they kill deer? Sure but thats not the role they were designed for and if you use them for that purpose you are risking some heartbreak. The .243 is the minimum for deer in my opinion and even with it you must be careful with your shots. The 22-250 is an excellent varmit round slash target round but thats all IMHO.