Since you own a gun...

Originally Posted by Spexxvet
When would actually use your gun to kill someone?

I would actually use a gun to kill someone when even if I didn't have a gun I would kill that someone anyway.

You can "what if" the topic to death; but, society evaluates each shooting as a unique set of circumstances. Sensible people use applicable laws and case studies to answer those questions for themselves. Among the things that case studies have demonstrated is that in the aftermath of any shooting, previous statements made by shooters in response to "what if" questions can be spun to work against them. It can be contended that a shooter was predisposed (i.e. already made up their mind) to act in a particular way regardless of the unique set of circumstances they faced in real time when a shooting occured. Even that which is learned through bona fide training by competent authority (e.g. law enforcement) should not be casually discussed in the context of "what if" situations. With all of the resources law enforcement itself has, it too at times has difficulty validating justifiable shootings. I don't think you will get many answers that specifically address your "what if" questions [at least I hope not].