I am a bit contrary on this. FMJ was used by the military since ? And we can kill people but not animals with it?
The Hunting regulations are written with the intent of humane quick kills. The military uses FMJ for exactly that reason, they are least likely to provide a humane quick kill. The Hague accords (often incorrectly identified as the Geneva Convention) prohibited soft nose (Dum Dum) type bullets for war. The intent was to reduce the suffering of the soldier when shot.
If you are using an 06 on 80lb animals, using FMJ is an option (where legal) but a better opotion is to use less gun for the game.