trying to understand power factor.
Can someone give me the "Idiots guide to Power Factor."? I'm interested in trying to get involved with defensive practical shooting competitions, but i dont understand the whole power factor consideration. Hoping to get an explanation in laymans terms although im not afraid of the math that may or may not be involved. I'm just confused about 9mm vs 40S&W vs 45acp. Im looking at starting in a production division, but not necessarily staying there. Just looking to get my feet wet. But i have several handguns and was just wondering about power factor and if i should bring one over another due to scoring. I'm honestly not trying to win anything, im a decent shot with all my pistols, but i think getting into some of these competitions may make me a better shooter. Just want more info into what i may be getting into.