I shot a deer and an antelope with these last year. Both were good shots and both animals died within seconds and in sight. I was surprised by the blood trail though, there was not a good trail on either one. Also, after going through an animal the blades were really easy to unlock, way easier than they were when I played around with them before hand. This led me to think that when going through an animal they came unlocked, this would mean the dull part of the opposite blade would partially obstruct the cutting edge of the other side. This may have been the reason for a less than good blood trail, I don't know. In the end these are still a mechanical broadhead and I didn't feel very confident in them though, so I switched back to a fixed blade.