You carry a gun for self-defense in the off chance you need to defend yourself or someone else against a violent attacker. Even though the probability of you having to use your gun is low, you know that it is far better to have it and not need it, then need it and not have it. But what about spare magazines? Can the same be said about carrying extra ammo?
Sure, because while many gunfights are over with very few rounds fired, many do not end until the attacker is hit with several rounds. Furthermore, there is an increasing number of assaults where we see multiple attackers. In these incidents, the number of rounds fired in self-defense quickly increases.
Am I making a case for an everyday carry (EDC) handgun with high capacity? Of course, especially when over the last few years, we have terrific 9mm sub-compact handgun options such as the Sig Sauer P365, Glock 43X/48, and the Springfield Hellcat. These small, lightweight, and shootable guns offer capacity over 10 rounds. No one has ever wished they had fewer rounds after having to use their gun to defend themselves.
Maybe you're thinking, 'if my gun has a 7-round capacity, and I carry a spare mag, I have just about the same number of rounds as someone who carries a Glock 19 with a 15-round capacity.' On paper you do, but there are some problems with this logic. First, anytime you change magazines you introduce a variable to the equation. What if under stress, injury, or circumstance that you cannot get to your spare mag or fumble the magazine change. It would suck losing the fight because you never got to your extra 7 rounds.
All this being said, I still think it is a good idea to carry a spare magazine if possible. Surely incidents where magazine changes are needed are rare, but if that is the situation you find yourself in, it becomes pretty darn important.
What if you cannot carry a spare magazine, or you carry a gun with a lower capacity, such as a 5-shot revolver? In this case, you must know the limitations of your gear. Firing a quick 3-round group of lead into an attacker's body has just taken up sixty percent of your rounds. And while we should always be thinking of using the gun in a way that gives us a way out, it becomes even more critical when you have two remaining rounds to deal with a secondary attacker or where those 3 rounds were not immediately incapacitating.
I think it is possible to forget the real reason we carry a gun in the first place. It is to protect life, right? So, the decision to choose one handgun over another should be made with as much information as possible.
You should have thoughtful answers to some basic questions. Questions like, why you choose the particular gun you carry? Was capacity a consideration? Why do you use that brand of self-defense ammunition? Does your EDC work with that ammunition? Do you have a manual external safety, why or why not? Does the safety come off as part of your draw stroke, or is it something you must remember to do? Then ask yourself, do you carry a spare magazine, why or why not.
Your answers to the above questions may be different than my answers, but you need to have good answers, not excuses. Answers such as 'this gun is better than no gun' do not show a logic-based decision. Remember you may have to rely on this tool to save your life. Stay safe.