Jumbo pellet. I have stood down many a charging 11000 pound elephant bull at full tilt! And buffalo's lions alike... But this pcp bug is something else. I have to budget carefully to make things work every day here in africa. But my goodness it's addictive every time you pull the trigger on that air rifle and hear the rush of air pushing the bullet forward and then see the hit, and then realise that this just came from an air powered "gun"!!! This is stuff dreams are made for. Well at least for me. Best regards.