Be nice if all these type of incidents could be recorded and catalogued. I guess most of it would have to be self-reported if no shots were fired.
There are about a thousand uses of guns to stop crime or in defense of self and others for each justifiable homicide.
The vast majority of the time, no shot is fired.
The FBI UCR records about 300 justifiable homicides by non-police each year. There have been studies that are consistent in showing that the FBI UCR only catches aobut 20% of Jusifiable homiciedes, for a number of easily understandable reasons. Thus, there are likely about 1500 justifiable homicides each year.
That does not take into account the number of justifiable homicides where no suspect for the homicide is ever arrested or identified.
40% of homicides are never solved. If the same percentage of those are justifed (likely larger, because most homicides are altercations between violent criminals, and they are the least likely to report) that would bump up the likely justifiable homicide number to 2500.