OK so maybe this is kind of a dumb question, but my curiosity has been killing me so I thought I'd post this here and see if someone with expertise in physics can help me. I'm a history buff, and a friend of mine mentioned a story he heard about a Napoleonic War-era cannon being pulled out of a museum and used during the defense of Moscow in World War II because the situation was so urgent. He wasn't sure if it was true or not, but that's beside the point. This made me wonder... what would happen if someone loaded up http://en.wikipedia.org/wiki/Dardanelles_Gun" [Broken] and fired it into a modern tank? The Great Turkish Bombard could fire a 550 kg projectile that was 63 cm in diameter. I don't know what kind of muzzle velocity it could achieve, but some 15th century cannons could reach around 250 meters per second. A http://en.wikipedia.org/wiki/T-72" [Broken], just as an example, has 500 mm of composite steel armor. Would the blast dent the tank? Would it move it or even penetrate the armor?