Can I use a MatchKing bullet for deer hunting? They shoot just great in my rifle, so they should be just super for hunting use, right?

No, it’s not recommended. The MatchKing bullets are designed for pinpoint accuracy; with no consideration given to what might happen after impact. If the bullet has arrived on target accurately, its job is done at that point. Hunting bullets must perform in a certain manner after impact. Penetrating ability, expansion characteristics and even profile must be considered when designing a hunting bullet. Use MatchKings for matches, and game bullets for hunting.