I'd rather have an MP5 with a 15 round magazine than a Glock with a 30 round magazine. I'd rather have an M1a or G3 with a 10 round magazine with 8 rounds loaded than a high capacity auto loader handgun with 15-20 rounds in it.
At some point, the issue becomes the ability to control the weapon in combat, at some point firepower becomes more important. If you get into a bad situation, you don't need more rounds for a smaller, harder to control handgun that has limited terminal performance. You need a better gun, not just more rounds.
The MP5 (or semi auto equivalent) vs Glock example I listed above is a golden example. Same cartridge, but how much more effective is an actual PCC or SMG vs a pistol? With greater stability, you can aim better, follow up better, make those shots count better. 15 rounds in a carbine of the same caliber is going to do you better in any combat situation.
In a fight against one attacker, the more stable gun is better. In a fight against many attackers, moving and shooting, under stress, how effective is that handgun firing multiple rounds at multiple targets? Before one of them hits you? Before you have to get to cover, or over run them? Or they try to over run you? Are you trying to kill them, put them out of the fight, pull a retreat under your own fire?
That's why "high capacity" handguns are over rated in reality. What is the magic number? 13 from the Hi Power apparently isn't good enough anymore, for some magic reason. 15? 18? 20? Goofy extended 30 round stick magazines in your pocket? And, how many of those rounds can you use effectively against multiple attackers in a real life fight? Really? Not just comparing numbers to numbers on paper.
More capacity, without affecting reliability, is always a good thing. But it isn't the winning, dominating advantage some seem to think it is. The revolver trusim of "if you can't do it in 6 shots, you can't do it at all" is a smartass saying that isn't true, but isn't exactly false. The answer to missing targets, or not wounding them enough to put them out of the fight, isn't more missed shots or weak under powered ones.
If you "need" a 20 round magazine in a handgun, you need a rifle, a shotgun, a machine pistol, or a machine gun. If you expect four armed attackers, you need the same.
The limitations of the handgun mean that capacity isn't its greatest limitation. And more capacity won't save itself from those limitations.
I have nothing against people who carry high capacity magazines, they are just fine. But the idea that they have the upper hand because of it, or will prevail because of it, is nonsense.
