I never plan to handle a crowd of muggers, zombies, or a motorcycle gang.
I never plan to get in a shootout at all, not even with one guy who was a bad shot before he went blind and has only one round of .22Short in his tiny pocket gun with no sights and a 35lb trigger pull. But I carry a gun anyway and I even load it. It's been my experience that reality cares little about our plans. It serves up what it's going to serve up regardless of what we plan for.
If you have to carry 20 , 30, or 40 extra rounds , it is a clear indication that familiarizing with your EDC is in order.
First of all, nobody HAS to carry any rounds at all. Nobody even HAS to carry a gun. People choose to carry a certain number of rounds. Some based on their favorite movie, some based on statistical analysis, some based on a past bad experience--or maybe reading about someone else's bad experience, some because that's all they can manage, some because that's what's easy for them, some just because.
Second, no amount of familiarization with your EDC will make it capable of dealing with more determined attackers than there are rounds in the gun. Even the best shot in the world is in a lot of trouble if he's facing down 3 determined attackers and has a 2 shot derringer. And planning to make every shot a hit might not be a great idea--reality always gets a vote. In the real world even good shots miss occasionally, and the odds of missing go up with stress, movement, injury, poor lighting, and/or trying really hard not to get shot while shooting back.
Lance Thomas won his first gunfight using a 5 shot gun against 2 attackers--it took him 3 shots to neutralize one attacker--lucky for Mr. Thomas, the second attacker backed down. Thomas decided he didn't like relying on luck so he prepared differently going forward. That preparation stood him in good stead--his next gunfight was against five attackers. He fired 19 rounds from 3 different guns, killing two of his attackers--the others fled. He did miss a number of times. Some might think that was understandable since he was shot 4 times at the outset of the fight before he was even able to return fire. Of course, here, we know better, he said sarcastically. The fact that he had to fire 19 rounds to resolve a gunfight against 5 attackers is a "clear indication that" he needed more familiarizing with his self-defense gun.
I'm not going to tell anyone how many rounds they need to carry. But I do think it's important to keep in touch with reality. What does that mean?
The scenarios we do or don't plan for don't control the scenario reality hands us. Planning for one guy who stands still and is very slow on the draw doesn't mean you won't get 3 guys who are quick on their feet and show up with guns already drawn. Or maybe 5 attackers like Thomas' second gunfight.
Planning to have perfect marksmanship in a gunfight is not realistic. People miss in gunfights--often they miss a lot. Banking on making one for one hits isn't wise.
Assuming an attacker will go down after a solid hit is not realistic. Even assuming that two solid center-mass hits will always be rapidly effective could result in more than just mild disappointment or surprise in a real-world gunfight.
Again, I'm not going to quote a specific number that is "best" because that's not how it works. It's just very important to have a realistic expectation of what a particular choice is likely to mean if things suddenly go sideways in a really impressive way.
