How Important is Capacity for a Self-Defense Gun?

by Charles

In the context of an armed civilian, which I am and will wage most of my readership is also, if I asked you to assert how much ammo would be required from a handgun to survive a potentially lethal attack on your person that was sure to occur, what would your answer be?

Two rounds? Three? Six, ten, more? What would you base your answer on? A feeling? Statistics and other measureable data? What? For such an evergreen topic of conversation among shooters, the answers that people offer seem to have more to do with their own personal philosophy or confidence than any quantifiable reasoning. And like so many other popular “hardware” based conundrums, people seem to be unassailably certain of their preference.

Instead of telling you what the magic number is, or who is wrong and why so we can all argue furiously about it in the comments afterward, I am going to instead give you some food for thought on capacity in the context of civilian self defense to help you make intelligent choices when selecting a firearm. This article will be all about capacity.

What does Capacity Mean to the Average Shooter?

I assert that most armed citizens and shooters only consider capacity in an incidental context when selecting a firearm. Sure, some may desire a given gun, say a handgun, for its plentiful amount of ammo on board, but most only view it as an afterthought compared to the gun’s other salient characteristics, like caliber or brand.

I am not making too big leap, here: for folks that want a .45, it is only natural that their gun will carry less ammo than one shooting puny, ineffective 9mms.

A person wanting the 9mm likely desires it because it has so many rounds on tap compared to the same size gun with a larger chambering. Revolver shooters get five or six rounds as a general rule and that is that.

Most of these shooters do not really consider the implications of capacity, and whatever their chosen gun has it will be adequate to the task because they believe it in their heart of hearts. Many or few, whatever amount of ammo their gun holds is fine.

What Capacity Really Means to You

As simply as possible, each round your gun holds, ready to fire, is an opportunity to solve a problem. “Solving the problem” in our case means striking our attacker with the result being his incapacitation or cessation of his attack. Specifically, greater capacity simply means more chances without having to manipulate the gun, i.e. reload.

That is about the simplest summation of the issue I can muster. Simple is good, but simplicity often sweeps the ever important Nuance under the rug. While each round ready to fire is a chance to solve my problem, not all of my chances will be weighted equally: I may fire and miss, even multiple times.

I might fire and deliver a perfectly lethal shot to my attacker, yet he keeps coming and I need to try and try again, or try a new solution. The attacker may bring his friends, other problems for me to solve, with him and now I may need to fire even more. Now suddenly a deep pool of “chances” is comforting.

Fortune might, though, favor me. I may fire, miss and the resulting thunder and light still sends my attacker packing. I might fire a single round or two, achieving only scratch hits, and our earnest assailant might still drop in his tracks as if struck by God’s own fist.

Unfortunately, I will not know any of this prior to the event. I hope I do not have to deal with the former, but will surely be thankful if I wind up with the latter.

There is no denying that capacity is important, at least desirable, to modern shooters in most circumstances. Manufacturers keep cranking out guns with greater and greater capacity, even in larger calibers like .45 ACP.

Extended magazines and bolt-on magazine extensions are popular items today, and it is a rarity to see a gun with stock capacity among the cognoscenti of any discipline or profession. But what does it truly mean?

Answering the Hard Question

Can we say that lower capacity guns will get you killed in the streets, that you’ll simply be outgunned by your attacker? And hot on the heels of that question, what is the minimum acceptable capacity for self defense? Does caliber make any difference in the calculus?

After all, if I am chunking big bullets, I can get by with chunking less, so long as they hit, right? And around and around we go back to the beginning complete with caliber debates and more derp than you can quantify.

Is this just one of those questions that doesn’t have any answer? It sure looks like it to many seekers of truth, but I do not think that is the case.

To reach anything approximating an honest answer, we at must consider the totality of the circumstances involving statistically average attacks on civilians and what a typical armed response results in.

It is often forgotten, these encounters do not occur in a vacuum! An armed robber’s motivation to hold-up a citizen or perform a home invasion is likely different from an enemy soldier on a battlefield, or even a criminal about to “go loud” and get into a gun fight with a cop in order to escape capture. This bears much consideration, and we’ll break into that in a moment.

Also, in my humble opinion, it is also worthwhile to stop and consider the personal philosophy of a given armed citizen before doing anything like making a sweeping proclamation.

The attitudes of a hard-charging and motivated student of the gun and an aging grandmother who just wants to keep her grandbabies and herself safe are very different.

Theory versus Reality

Your objective as an armed citizen is different from a cop’s, or one of our fighting men and women in the armed forces on a battlefield somewhere. If you are forced to fight for your life, your immediate objective is nothing more than to extricate yourself from that fight and avoid death or injury of at all possible.

You ultimately want to do that while also prevailing in the all-but-certain legal escapade that will follow your use of force, but leave that part out for now.

It does not really matter how I achieve the first part of my objective, be it run or fight by some other way or with some other weapon, but considering you are reading this article right now and are the kind of person who relies or will rely on a gun for self-defense, we can assume it will involve shooting the attacker.

It is assumptions made about this specific act and its potential outcome versus the potential reality of the outcome that lead to so much gnashing of teeth and gesticulating on this topic. Let me explain.

As I mentioned in the earlier sections, I might need to fire more than one shot to my attacker, for any number of reasons. Those reasons are valid, and have been borne out in many documented shootings.

But another possible outcome, even likely outcome of civilian shooting their attacker is that being shot, even shot at, may result in them fleeing or at least withdrawing from the attack. This outcome too has been documented in many, many self-defense shootings, and it, statistically, does not take very many rounds to reliably achieve that outcome.

Please keep in mind, crunching the numbers on all of this is something of a fuzzy operation as there is no convenient one-stop shop for accurate statistics, at least for civilians, but what data is available to all of us does paint a fairly reliable picture of an “average” armed self-defense encounter for civilians and I stand by my deductions.

Why? Remember what I said about the differing motivations of for-profit criminals trying to rob a victim for some material gain versus that of a criminal trying to avoid capture and lengthy incarceration or an enemy fighter on a battlefield?

Our scumbag mugger is likely trying to “do his job” and make money for whatever in the hell he needs it for. If the risk-reward ratio suddenly nosedives for them, precipitated by the intended victim’s outgoing fire, he has little to lose and more to gain by fleeing; there are plenty of less dangerous marks around the bend.

The other fighters I mentions, the criminal squaring off with the cop or the soldier at war, are likely far more motivated to fight on and hard as the penalty for failure is steeper any which way; they have less to lose by fighting on, or it is their job.

While motivation and intestinal fortitude is something that is impossible to measure among all these disparate participants, we can assume they are certainly different enough to influence decision making, all other things being equal.

In essence, a citizen is only concerned with stopping the attack, and the attacker, statistically, is keen to stop once he meets significant resistance from his intended victim.

Criminals fighting cops with lethal intent, or soldiers on battlefields endure far more resistance and wounds before succumbing or attempting to break and run, if possible.

Simply put, the nature and duration of the threat to a civilian is somewhat different than the threat to a cop or soldier. This means that an armed citizen is not operating under the same auspices of weapon selection as either of the others.

Just the Facts

Stay with me: if my objective as a citizen is to simply force the bad guy to stop his attack, so long as you have a gun you can, statistically (there is that word again), count on 1-3 rounds of any caliber being more than enough to do so should you hit him. Once hit, our bad guy is likely to start thinking escape versus pressing his attack.

A significant portion of them will do the same once you start firing in their direction. So relying on statistical probability, having a reliable gun of any kind and attaining proficiency with it is the single greatest contributor to a positive outcome once the attack has begun. Following this line of reason, even a 5- or 6-shot is more than enough to solve the kind of problem an armed citizen is faced with.

Essentially, once you start returning fire and especially if you get a good hit, you have a good chance of halting the attack by way of the attacker fleeing. Whether he is incapacitated or even killed is inconsequential; once the attack is halted and you can make your escape to safety, your mission is accomplished.


The above informs and illuminates the mindset of some of our gun carriers above; some of us, your author here included, care not the least about those particular statistics, no matter how comforting they ostensibly should be. This brings us back to the philosophical questions.

If I wanted to trust to statistics, I do not need my firearm at all, almost anywhere in America. The U.S. is so overwhelmingly safe compared to most countries (save a few neighborhoods and cities) that one must positively go out of their way to get waylaid. Since that is so, why carry at all?

Exactly. Just in case. I do not trust to chance, and furthermore I want every advantage I can get in all circumstances and in all times. I know I can gain advantage by careful selection of my defensive firearm.

What are some advantages that a good firearm can confer? Reliability, certainly. Adequate caliber is another. And, yes, capacity is one. There is simply no way around it, based on my reasoning above: I have to solve a problem, and I want as many chances as I can get as quickly as I can get them.

Think if it another way: if five or six rounds is adequate looking at average encounters, how is 10, 15 or even more not even better, assuming all other characteristics equal? Precisely. Of course it is better. No one has ever wished for less ammo when it was time to shoot in the gravest extreme.

Charles’ Advice and Tips

All of a gun’s characteristics must be weighed in total against the job you want that gun to do. I carry a fullsize 18 round pistol because I want to and more pertinently because I can; setting, attire, profession, the works all allows me to conceal such a gun, and I want the advantages it gives me.

It does no good for me to beat you over the head with the Gospel of the Fullsize Gat if all you could truly carry, or would carry, is a small revolver or semi in a pocket or purse. Your needs may be different than mine.

Capacity is one characteristic that may get the chopping block in a ruthless paring down of “Wants” against “Can get away with.” No matter what, you cannot cram 15 rounds into a subcompact semi-auto without increasing the size of the magazine and ergo the grip dimensions.

All but a few revolvers or revolvers chambered in tiny calibers are structurally limited to 6 rounds, 8 tops. There is no use wishing or crying for greater capacity if one of those revolvers is otherwise right for you.

I believe you are better off selecting a class of gun that will perform well in its role for you first, then considering models that offer good capacity in their class while still being mechanically reliable and possessing other desirable features.

I am a stalwart advocate of guns with more ammo on board, but even I would not see someone move away from an option that they are far more likely to carry that just so happens to hold less ammo.

Bottom Line

Based on all available evidence for civilian self defense a gun possessed of anything more than a 6 shot capacity is not a typical deciding factor for a positive outcome in an attack.

Nonetheless, additional ammo onboard is always an advantage so long as you do not compromise other essential characteristics for your needs in pursuit of more ammo.

The most important criteria for a defensive pistol are that it is reliable, you attain proficiency with it and you, above all, have it with you when you need it.


Capacity is always going to be something shooter’s argue about, obsess over and analyze. But for civilian self-defense any gun holding 6 or 7 shots is very likely to be enough to do the job so long as its wielder is competent.

You will never regret having more ammo in the gun, and if you are particularly unlucky you may have need of it, but the vast majority of civilian attacks will be concluded within a handful of shots.

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8 thoughts on “How Important is Capacity for a Self-Defense Gun?”

  1. Capacity depends on whether one is going to War or intending on use for self defense.

    I’ve carried a 5-shot .38 Special revolver for more than thirty years in nine different States.
    Used it for self defense four separate times.
    Faced three individuals three times.
    Faced four perpetrators once.
    Never fired a shot.
    Mere presentation of the weapon did the trick.
    The four perps got clean away.
    The other three were picked up.

    That said, as a Citizen, I own an AR-15 with a thirty round magazine to fulfil my duty as a Citizen soldier should the need arise.

  2. I carry a .45 and two extra magazines giving me a total of 35 rounds.
    The national average of hits by the Police is 17 to 18 percent this means that 82 to83 percent of their shots miss.
    I hope that my marksmanship would be better but never being iin a situation to test it I have to go on those figures as the only information available.
    One the range I usually shoot a big raged hole, but I’m not shooting under stress.

  3. My EDC is one of two .45 ACP guns, S&W 457 or Ruger P345. I carry multiple reloads, sometimes a second gun. When I travel, I usually have a revolver back-up, either a Smith &Wesson Governor or Taurus Judge Public Defender. I like the versatility of large caliber bullet and multiple projectile round. Although the 1992 LA Riots were so long ago, I am still haunted by that video of Reginald Denny being pulled from his truck and pummeled by those Satanic minions. I don’t know why I hold on to those horrible images?! I was nowhere near when the riots kicked off. I don’t know anyone attacked there. Regardless, I consider that type of situation in planning the defense of those in my vehicle.

    • I agree, with today’s political climate you never know when you turn the corner at the next intersection there could be a massive crowd of antifa thugs or some other group destroying property and causing trouble.

  4. It depends on which hand gun I choose to carry for that day.
    My Ruger 9mm has a 17 round mag so I carry one additional mag.
    My S&W .357 magnum I carry two speed loaders
    My Springfield .45 I carry two additional mags.

  5. I’m one of those everyone looks down on for carrying a “mouse” gun. It’s a Beretta 32 with one in the barrel and 7 in the magazine with a spare magazine. I chose it precisely because it’s smaller and easier to carry. I can handle it quite nicely and it doesn’t weigh me down. I use a walker so I need something easy to carry if I am going to do so. I chose to do so because I don’t want to be a victim and if I have to defend myself or my wife I want to have the means to do so and this allows me to have it handy instead of being back in the car or at home because it was to tiring to carry. At home I keep a Ruger GP100 4″ in .357 mag. at my bed and a Mossberg 500 in my computer room along with my Redhawk in 44 mag. Carrying even the GP100 weighs me down and tires me out much to quickly to be practical for me. I can hit center of mass and forehead on a person shaped target very quickly but like others have said, I’ve never had to shoot in a self defense situation. I pray that I will never need to do so.

  6. All things considered, you use what you need to use. If you have 15 rounds in your gun, and 3 stops the threat, then that’s all you needed. The remaining 12 is insurance, just in case it takes more then 3. If the weight and size increase over smaller capacity guns are acceptable insurance premiums for you then by all means carry that large and that many. One thing that is rarely brought up though, is if you are in a state where any sort of civilian firearm carry is illegal, the size of the gun and it’s un-detect-ability become much more important. If you choose to carry anyway, then you would want to keep that your little secret, to yourself, especially from law-enforcement. You also have to make sure, you can keep your head enough when things go down, not to give away your secret for unjustified reasons. Justified or not, if you pull your gun in one of these states, you have broken the law and are going to jail. But better to go to jail alive then in a body bag going to the morgue. So what do you do. Very simple. You only use it defending yourself or someone else against SERIOUS BODILY INJURY OR DEATH, period end of story. If you witness a minor assault, robbery or theft, call 911. If someone is calling you out but not attacking you, just walk away. Unfortunately if you do get attacked, you now fall into a quandary, even if your attacker is unarmed, if he overpowers you, he could take your gun and use it against you. So do you shoot or hope you can overpower him. That would be $64,000 question. If you can, run away if you have to. You are not running away from your attacker, but from going to jail. Of course in your home it’s a whole other thing, you can legally have your gun there.

  7. One question outside of capacity should be caliber despite what some people say a larger cal bullet like a 45, 357, or 44 magnum, does have devastating consequences if you are hit with it. Heck, that’s why the 45 was invented!! The sound and flash which accompanies these calibers are like wise intimidating. Just FYI



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