people can easily shatter padlock shackles with ramsets, which are basically little blank round gunpowder powered hammers. not sure if a gun would, but sure seems like it.
also, the asteroid one is probably quite true, but saturns ring are between 10m and 1 km in thickness, so there are exceptions.
The Slowmo Guys released a video on YouTube recently where they shot a pistol at a padlock not really expecting it to break, but it did, haha! I think it took a few rounds though.