here are some things for you to think about. if a fmj bullet goes through an animal and dosen't open "it isn't supposed to" the bullet dosen't have much friction to slow it down so it comes out a lot faster then a bullet which will open up and lose almost all it's K.E. and speed inside the animal. think about it. that is 1 reason why they will ricochet more then other bullets

reason #2- on a miss if a bullet hits a rock the tip should push into the rear of the bullet opening it up just like it would in an animal and this will cause it to lose it's energy. where a fmj bullet isn't supposed to open up so there is a much greater chance it will hit and not lose much energy and be deflected into the unknown.

now don't get me wrong i'm not saying that fmj's won't open up or fragment but they are not supposed to so chances are that most of the time they won't. think about it the reason you suggested using them was that they aren't supposed to open up so the exit should be almost as small as the entrance.

if you don't believe me run some test and do some research