Another warning shot thread?
No professional trainer, or knowledgeable person would advocate relying on a loud harmless noise to frighten a criminal who's weapon would be loaded with real bullets.
Yep. And I always find it amusing when someone suggests that racking the slide of a scattergun will scare the bad guy into soiling his pants and running away. Fact is, when you "warn" your adversary in a combat situation, you've just abandoned the most important advantage you already possess over him - that of surprise.