I had a NAA .22/.22Mag swappable cylinder revolver for awhile. Tiny, super hideable, and with the .22Mag, LOUD! And 2 foot flame. It would scare anyone around when it went off.
Turns out, you can fan the hammer. Yes, it will take skin off. It’s a belly gun, and if you have to use it, use it from 7 feet or less, fan it, don’t extend uour arms much, dump 4 of the 5 into said bad guy.
Boot gun. Last resort.
The report and flame would certainly add to the deterrent effect.