Mine are very combative also, they attack my wallet.

First mistake – assuming you know how a defensive encounter will play out. This is like the anti-gunners saying “limit magazines to 5 rounds, no one needs more than that.”

I had one encounter, I’ve related before, where I went through all three of my 15 round mags, had three rounds left by the time the second bad guy went down and he still had several fully loaded magazines available. If he had not gone down when he did, after I needed to fire those last three rounds if they didn’t do the trick my wife and I would have died that day. This was after putting rounds in each of the two bad guys, one guy was down but still alive (but paralyzed due to a few round shot placement), the second guy even though wounded with several rounds in him was still up and engaging and I had advanced on him and finally when I was finally only several feet from him, after advancing over the 30 yards to get to my wife, he went down. Over half of the ammo I fired hit the bad guys – it was a moving fight, me advancing from cover to cover to save my wife from them, one of them firing at me, I still managed to put over half my shots in the bad guys when they exposed any part of their self from the cover they had.

I had never thought until that day that I would ever use that much ammo in defensive encounter. After that I started carrying six 15 round magazines, I used a Glock 22 .40 cal that day, that was my EDC for 20’ish years. I’ve since retired that gun and due to a change in the needed carry method I’ve moved to a Sig P-365 X-Macro Tacops as my EDC now and carry six of the 17 round magazines for that.

Lessons learned that day: First, and possibly last mistake you will ever make because this mistake can be fatal to you – never assume you know how a defensive encounter will play out, do not plan for how you think it will go but rather plan for how it can go as if every case will be the most extreme problem.