You do not state the caliber , however, the standard XTP has a floor threshold velocity of 850 and 800 fps for the standard .44 and .45 caliber bullets respectively. The mag .45 caliber bullet has a floor threshold velocity of 1,200 fps. (5th Edition Hornady manual)

If a bullet you shoot begins to get close to these velocities, its tendency will be to act more as a solid than an expanding bullet. Considering both bullets are nearly one-half inch in diameter, this should not be a problem as long as your bullet passes through the animal.