A 30 cal Bully is plenty powerful for what you need. Out of the box brand new hatsan has those set up hot, shooting a 44.75 grain Vortex pellet at 1075 FPS. I had to dial mine down 11 turns on the hammer screw to get it at 876 FPS for around 22 shots, or a bit over two magazines. Plus, field supply has those pellets on sale every couple of moths at $10.50/tin of 150. With that price, I don’t mind target shooting all day. I don’t think I’d do the same if I had a .35 or larger, as now I see dollars hitting the pellet trap instead, lol.