There are at least five bullets stuck in that revolver barrel. RugerForum members seem to think is a Ruger Blackhawk in .357 Magnum. The squib loads could have been low powered .38 Special rounds or very badly loaded .357 rounds. That the shooter did not notice it after the 1st, 2nd, 3rd or 4th round is crazy!
It is hard to see if there is a bulge in that barrel, a symptom of a round fired into a blocked barrel. I think if had been a semi-automatic pistol there would have been a disaster. A revolver can vent gas in the gap between the cylinder and the barrel but in a autoloader pistol for a brief period of time the gas has no where to go and the pressure build up would be considerable.
A few weeks ago I was shooting some old .22 Longs out of a rifle which I had not fired them out of before. I nearly crapped my pants after the second round when I realized to forget to check the spotting scope to ensure that the first round made it out of the barrel and hit the target. I was shooting iron sights and could not see the target. I learnt a good lesson. Always make sure you hit the target, especially when you are shooting low powered ammunition.
Thanks to Advocate for the link.Related