We consider the effect on the adiabatic gravitational collapse of stellar cores of large mass due to (1) the use of different equations of state and (2) the inclusion of energy loss of shock. We find that different equations of state give very different central densities at rebounce and amplitudes of rebounce. When shock energy loss is not considered, all the equations discussed here will lead to explosions, but when it is considered, small amplitude rebounces will not do so.