Video: Please don't ever do this at home. Or do this anywhere, really. Mixing bullets with molten aluminium creates a helluva explosion -- but it sprays the hot liquid metal everywhere, and that's just a terrible idea. Plus, it's guaranteed to end in fire and blood. Instead, watch the Backyard Scientist do it. In the video below, he tosses 15 bullets at a bowl of molten aluminium and luckily, only three make it in, because the resulting explosion is so huge that I can't even imagine the bomb that would have gone off if all 15 made it in.
One cool sequence in the video is that you can see an individual bullet make contact with the molten aluminium and then immediately jump right out of the bowl and explode into pieces.