I assume you are talking about 9mm in a handgun. If one was going to hunt deer with a 9mm pistol, I would pick a bullet that offers a good combination of weight and expansion like a 147 grain Speer Gold Dot or hard cast with a big flat nose. Keep the distance 25 yards or less and only take a broadside heart/lungs shot and you should be good, especially on a smaller deer without alot of muscle mass. Now, 9mm fired from a carbine with the right bullet is certainly adequate under 100 yards or so, velocity is similar to a .357 revolver. One fellow on the Cast Boolits forum has taken quite a few with his 9mm Ruger PC Carbine.
