I would (personally) keep the .223 bbl on there. The Federal 60 gr. Nosler Partition IS a great bullet to use and should most definately put a deer down. If you are really uneasy about it, I'd say go grab a .243 barrel. Actually if you don't like .223you might be better off getting a different rifle for deer hunting. check gunbroker.com or some other auction sites. Maybe even the huntingnet free classified ads