I would say it depends on the shot placement. A good shot in the vitals from either will the job quickly, but I would also say you have more room for mistake with a gun. So, if that is what you are talking about, I would say a gun. But, the deer I have killed with a bow have covered a short distance after the shot on average than the deer I have shot with a gun. I don't think you can really compare the two. Now ask, which has more killing power, a .308 or 30/06 and you will havea real discussion.