Do something to pad that gun while practicing. Folded towel, foam, whatever. Wear ear protection and a pad or you may be programming yourself to flinch. Which means a bad shot. When you're hunting you'll never feel it but you don't want to be flinching because of the beating you took while practicing. If it starts to bother you stop shooting and come back later. It's better to practice right a few times than practice wrong often.