Smashing a 50 cal round is going to cause all kinds of hell. The bullet does come out, but usually not far at all. I've seen 30-06 rounds get thrown in a wood stove more then once. The case bursts and the bullet hits the metal inside. Part of training for many firefighters includes addressing the fact that ammo is in many homes. They still fight the fire, because its proven that the bullets don't fly like if they came outof a chamber.