Hey Brian. Used a 3/8 steel shot with the RR2 bands. Same kind Tru-Mark has on their site. Was about 20 or so feet away, hit dead (no pun intended) center between the eyes. Had to use a slingshot because it was in the bikes on one of my buddy's porch. To close to use anything else without worrying about a fearful ricochet. Admittedly it was already sick and probably on it's last leg, but to be safe I was backed up by two people, one with a shovel and one with a pitch-fork, in case it just got really POed and came after me. Everything else I just get as close as possible and good shot placement (lot's of practice). Have used 38 cal. bullets before, but to much weight is as bad as not enough.