I'd like to add a bit of a different experience. I did the "Tap Rack...." thing but didn't get a "bang". I had a squib round, probably a reload I got at a show. The thing that saved me from a "KaBoom" was that the bullet hadn't gone far enough into the rifling to allow the next round to chamber.
It's only happened once to me but was enough to make me stop and think.
Best,
Rob