What I love the most about this video is that you can see the pressure building up behind the load before the casing finally bursts. It’s a great illustration that gasses, not an explosion, propel the projectiles down the barrel. There’s an old myth that a shotgun shell doesn’t have enough power to penetrate a cardboard box if it goes off outside the chamber, and this seems to add some plausibility to the argument. Either way that’s some great slow motion video right there.
[h/t hoboguy7996]