I used a 165 gr core-lokt on a deer last year and never did find him due to him running into a swamp. But i did find good amounts of blood on ground. At the end of the day i blamed my poor shot and not the ammo. I will say this , i have been using sierra game kings / and game pros and they have been more accurate than any other bullet i have tried. They are also cheaper or the same as core lokt. Also i do not like the package the core lokts come in. The Seirras come in a plastic case and the bullets are more uniform than the core lokts. IF you already have the core lokts i wouldnt worry about it but check out those sierras.