If the lowest legal bullet is .23 than that would meana bullet has to be a .230 caliber or above to be legal. The .223 is .07 short of being legal. Personally I wouldn't use that gun on any northern deer. Too much risk in wounding a deer. I hear people say they have dropped many northern deer with a .223 but a bullet that size is way to small to deer hunt with. I'll stick to Coyotes with my .223.