# How much does caliber matter in self-defence? **URL:** \ **Category:** Factual Questions\ **Created:** [May 12, 2007, 8:16am UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822 "2007-05-12T08:16:03Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![enipla](https://avatars.discourse-cdn.com/v4/letter/e/54ee81/32.png) [@enipla](https://boards.straightdope.com/u/enipla)\ **Post date:** [May 13, 2007, 12:23pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/41 "2007-05-13T12:23:11Z")
For a personal home defense weapon used to ward off a robber, I don’t really think the caliber matters that much. Think about it. How many robbers are going to try to confront you if you are shooting at them with anything. Now a crazy person that has the intent to harm you is a different story. I was looking at a .22 magnum for my Wife (she prefers revolvers). But I discovered that the trigger pull for rim-fires in double action mode is pretty heavy. So, I am considering a .32 H&R mag, or a .38spl. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [May 13, 2007, 12:33pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/42 "2007-05-13T12:33:44Z")
[QUOTE=Euthanasiast] As someone who has been on the giving and receiving end of kicks, knees, elbows, headbutts, and the like, I must respectfully disagree. [/QUOTE] I was referring to a gun-on-gun fight, not traditional H2H. [QUOTE=Euthanasiast] The reason people stop or fall after being hit by a bullet is due in large part to an absorbtion of a tremendous amount of energy dictated by mass and velocity from the round. This is where the majority of your ‘stopping power’ comes from. [/QUOTE] No, this is not correct. First of all, there is no such thing as “energy dumping” when it comes to handgun rounds. The primary killing mechanism is the tearing & severing of organs, muscles, blood vessels, nerves, and various body tissues. Much like what a knife does. Secondly, my statement “people often fall (after being shot) because it’s what they think they’re supposed to do” is backed up by FBI research. In [this](http://www.firearmstactical.com/pdf/fbi-hwfe.pdf) paper the FBI says, > [@](#): > > it appears that many people are predisposed to fall down when shot. This phenomenon is independent of caliber, bullet, or hit location, and is beyond the control of the shooter. It can only be proven in the act, not predicted. It requires only two factors to be effected: a shot and cognition of being shot by the target. Lacking either one, people are not at all predisposed to fall down and don’t. Given this predisposition, the choice of caliber and bullet is essentially irrelevant. People largely fall down when shot, and the apparent predisposition to do so exists with equal force among the good guys as among the bad. The causative factors are most likely psychological in origin. Thousands of books, movies and television shows have educated the general population that when shot, one is supposed to fall down. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [May 13, 2007, 12:39pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/43 "2007-05-13T12:39:23Z")
[QUOTE=msmith537] I’m sorry, but do you have any cites for any of your advice? I’m not an expert or anything, but it seems to me that you shouldn’t have any problems unless: a) the weapon is illegal b) you went overboard in your administration of deadly force (like shooting the dude 10 times) c) the situation was not clearly life threatening d) some other circumstances would lead the police to believe you are being less than truthfull [/QUOTE] In an ideal world you would be correct, **msmith537**. But we live in a hyper-litigious society, and you will very likely get sued. Even if the shooting was 100% justified. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [May 13, 2007, 12:48pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/44 "2007-05-13T12:48:03Z")
> [@](#): > > If he was hit in a non-vital part of the body, why would he stop? Yep. Even if the bullet goes through the bad guy’s heart, he can still fight for up to 20 seconds. And this is where Hollywood has it all wrong… they always show the person falling down right away. This makes people \*think \* that they \*should \* fall when shot. The repercussions of this psychological programming are both good and bad. If the bad guy falls right away after being shot (because that’s what movies have taught him), then it’s good. But if \*you \* fall right away after being shot (because that’s what movies have taught you), then it’s bad. ---
**Author:** ![Dunderman](https://avatars.discourse-cdn.com/v4/letter/d/ecb155/32.png) [@Dunderman](https://boards.straightdope.com/u/Dunderman)\ **Post date:** [May 13, 2007, 1:29pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/45 "2007-05-13T13:29:23Z")
[QUOTE=mks57] If he was hit in a non-vital part of the body, why would he stop? [/QUOTE] I was figuring mainly pain, shock and kinetic energy. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [May 13, 2007, 1:52pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/46 "2007-05-13T13:52:50Z")
[QUOTE=drachillix] Nope > **[M1911 pistol](https://en.wikipedia.org/wiki/M1911_Colt_pistol)** > > The Colt M1911 (also known as 1911, Colt 1911, Colt .45, or Colt Government in the case of Colt-produced models) is a single-action, recoil-operated, semi-automatic pistol chambered primarily for the .45 ACP cartridge. The M1911 pistol originated in the late 1890s as the result of a search for a suitable self-loading (or semi-automatic) pistol to replace the variety of revolvers in service at the time. The United States was rapidly adopting new firearms; several new pistols and two all-new serv... Was already in service for 35 years before the US saw any serious action in the Phillipines. [/QUOTE] Nope. The [Moro Rebellion](http://en.wikipedia.org/wiki/Moro_Rebellion) started at the end of the Spanish-American War. We were involved in the Philippines long before WW2. ---
**Author:** ![BlakeTyner](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@BlakeTyner](https://boards.straightdope.com/u/BlakeTyner)\ **Post date:** [May 13, 2007, 4:34pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/47 "2007-05-13T16:34:41Z")
[QUOTE=Crafter\_Man] In an ideal world you would be correct, **msmith537**. But we live in a hyper-litigious society, and you will very likely get sued. Even if the shooting was 100% justified. [/QUOTE] Hence the movement in recent years to apply civil immunity to the Castle Doctrine laws - in Texas, for instance, after September 1, Castle Doctrine takes effect along with civil immunity (originally when the bill was drafted, it was an “affirmative defense” but, fortunately, the wording was changed to pure civil immunity.) I agree, though, with the 25k figure; that’s pretty common advice within the CHL/CWP community. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [May 13, 2007, 5:27pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/48 "2007-05-13T17:27:26Z")
[QUOTE=silenus] Nope. The [Moro Rebellion](http://en.wikipedia.org/wiki/Moro_Rebellion) started at the end of the Spanish-American War. We were involved in the Philippines long before WW2. [/QUOTE] I was going to point that out, but technically he’s correct. The 1911 came after the Moro Rebellion, so the next time the US used the 1911 in serious action in the Philippines _was_ in WWII. 😉 Although he did say ‘_any_ serious action’, so in that case you’re right. ---
**Author:** ![Bobotheoptimist](https://avatars.discourse-cdn.com/v4/letter/b/919ad9/32.png) [@Bobotheoptimist](https://boards.straightdope.com/u/Bobotheoptimist)\ **Post date:** [May 13, 2007, 5:30pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/49 "2007-05-13T17:30:43Z")
[QUOTE=Priceguy] Following this thread with great interest. So, in short, it is quite possible and not even improbable that I might shoot an ordinary non-doped-up guy running at me and he’d keep coming? [/QUOTE] In the training I’ve received it is repeatedly stressed that you keep shooting until the person is neutralized. With all the talk on the internet about one-shot-stop, no one I know puts any faith in it except as a reference point. A creature can shake off a lung shot and keep going for far too long (speaking as someone who has seen deer and antelope do so), Massad Ayoob has shown a knife wielding mainiac covering something like 20 feet in a second, so we practice double-taps and 2 and 1’s. A calm, cold-blooded shooter in a non-combat situation could take the time to get the perfect shot, but not usually in a self defense situation. ---
**Author:** ![BF](https://avatars.discourse-cdn.com/v4/letter/b/b5ac83/32.png) [@BF](https://boards.straightdope.com/u/BF)\ **Post date:** [May 13, 2007, 5:34pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/50 "2007-05-13T17:34:38Z")
[QUOTE=drachillix] Take another look at that site/cite, thats more like a plate at 12 _yards_ Thats also for improved cylinder choke which is uncommon outside of trapshooter circles most shotguns you find on the shelves are full or modified choke that are considerable tighter patterns. [/QUOTE] Just a clarification **drachillix**. You’ll find a predominant number of IC chokes on the skeet field or sporting clays, not the trap field. The widest choke I’ll shoot is modified, and that’s the first barrel when shooting doubles. Anything else it’s full, trap full or extra trap full. And almost all modestly priced shotguns that you can buy at Wally-world or K-Mart come with more than one choke tube, usually IC, Mod and Full. ---
**Author:** ![MrJackboots](https://avatars.discourse-cdn.com/v4/letter/m/c0e974/32.png) [@MrJackboots](https://boards.straightdope.com/u/MrJackboots)\ **Post date:** [May 13, 2007, 5:51pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/51 "2007-05-13T17:51:54Z")
[QUOTE=Stranger On A Train] I was just going to say the same thing. The FBI’s rating system for the _stopping potential_ of calibers emphasizes penetration. Note, however, that you don’t want excess penetration, as a bullet that penetrates through and through both fails to apply maximum energy to the target and poses a threat to bystanders. \ The FBI eventually concluded that the 10mm Auto round offered the best of both worlds–penetration and expansion–but discovered the pragmatic reality that the high recoil and large size of handguns chambered for the 10mm Auto were excessive for even average-sized agents, much less shooters with small hands or weak grip strength. (Anyone who has fired one of these monsters will know what I’m talking about.) [/QUOTE] A Special Agent in the Firearms Training Unit wrote up a set of notes on the decision to choose 10mm Auto (FBI load, which eventually cased down to .40S&W - full load is indeed a monster of a gun), which looks to be a fairly good reference. Choice quotes: Regarding penetration: _“Minimum 12 inches penetration, & 18 inches is better.”_ _Third, as our testing shows, even the most frangible bullets designed specifically for shallow penetration will plug up when striking wood or wallboard and then penetrate like full metal jacketed ammunition. We are aware of successful legal actions where an innocent party has been struck by a shot passing through a wall, but as we have proven, ALL of them will do that._ Regarding caliber: _“Given desired penetration, only way to increase effectiveness is to make hole bigger.”_ Regarding shot placement: _“If shot placement was all that mattered, we could arm all Agents with .22’s.”_ _A good example is killing a 400 pound pig with a .22, something commonly done on the farm. If the shot placement is exactly right, the pig is instantly killed. If it is off less than an inch, the pig goes wild and the process of killing it becomes rather lengthy and involved, whereas a larger caliber would succeed with a larger margin of miss than an inch. (Larger calibers are not used because they ruin too much of the pig - a consideration that does not come into play in a shooting incident - and besides which, nobody is going to die if the pig is not killed instantly anyway. In shootings, just the opposite is true._ ---
**Author:** ![RickJay](https://avatars.discourse-cdn.com/v4/letter/r/bb73d2/32.png) [@RickJay](https://boards.straightdope.com/u/RickJay)\ **Post date:** [May 13, 2007, 6:05pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/52 "2007-05-13T18:05:22Z")
[QUOTE=Crafter\_Man] A6. The only way to \*immediately \* stop the bad guy is for the bullet to penetrate his brain or spine. But unless you’re a master shot, it is advised to aim for his chest. 1. Keep squeezing the trigger until the threat is gone. Front sight, squeeze, rinse & repeat. 2. The main reason people fall after being hit by a bullet is because they think that’s what they’re supposed to do. They have been subconsciously programmed by countless movies that “a person always falls immediately after being shot.” But unless you are hit in the brain or spinal cord, there is no reason for you to immediately drop to the ground. So if you are hit with a bullet, try your best not fall down. _Keep fighting_. [/QUOTE] Do you have any cites or backup for these claims? #8 sounds like the most ridiculous sort of bullshit to me, and are you really saying a shot THROUGH THE HEART won’t stop someone immediately? Because, ya know, people without functioning hearts generally stop moving. How many times have you personally been shot and kept fighting? ---
**Author:** ![Euthanasiast](https://avatars.discourse-cdn.com/v4/letter/e/6f9a4e/32.png) [@Euthanasiast](https://boards.straightdope.com/u/Euthanasiast)\ **Post date:** [May 13, 2007, 10:48pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/53 "2007-05-13T22:48:21Z")
[QUOTE=Crafter\_Man] No, this is not correct. First of all, there is no such thing as “energy dumping” when it comes to handgun rounds. The primary killing mechanism is the tearing & severing of organs, muscles, blood vessels, nerves, and various body tissues. Much like what a knife does. Secondly, my statement “people often fall (after being shot) because it’s what they think they’re supposed to do” is backed up by FBI research. In [this](http://www.firearmstactical.com/pdf/fbi-hwfe.pdf) paper the FBI says, [/QUOTE] So tell me, just what movies were all those deer and hogs watching (that were shot through no vital organs or indirect to their central nervous system) that trained them to drop like a sack of hammers upon being hit with a high powered rifle round? Granted many deer or hogs do manage to take flight upon impact, but I have seen many that hit the ground immediately and did not get back up. These animals had to be shot again to bring about death, btw. People falling because they were trained by television to do so is absolute crap, regardless of what your paper says, because there are people all over the world and throughout history that have been dropped by rounds that were not life threatening, having never seen a single film or television episode of **Starsky and Hutch** , or even a television at all, for that matter. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [May 13, 2007, 11:35pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/54 "2007-05-13T23:35:39Z")
Theoretically, making a bullet faster is better than making it heavier, as the total force is mass times velocity(squared). If a bullet’s weight is doubled and it is fired at the same velocity, the impact will double: but if the velocity is doubled and the mass remains the same, the impact will quadruple. I believe that was part of the rationale for making the M-16 a much smaller caliber, but higher velocity, weapon. There were other factors too; including that the average soldier could carry more m-16 rounds than m-14 rounds, and that accuracy at long range (which is generally better in larger rounds) was not particularly important in most combat situations. I have read many stories of soldiers who dispute this however, and prefer heavier bullets because they do more tissue damage. Was there a point at which M-16s and/or their ammo was re-designed to make the rounds _tumble_, making the tissue damage factor more equal to larger rounds? I seem to remember reading something to this effect. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [May 13, 2007, 11:46pm UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/55 "2007-05-13T23:46:06Z")
[QUOTE=Priceguy] I’m armed, and a random psycho is coming at me. I shoot. How much does it really matter, at that particular moment, if I shoot him with a .22 or a .50 Desert Eagle, provided the guy isn’t on some ignore-the-pain drug trip or otherwise specially capable of handling a bullet? An average person will go down from a small bullet, right? [/QUOTE] At this point in the thread I’m sure that someone has pointed out that most modern military rounds _are_ .22 calibre, right? The standard 5.5mm round is for all intents and purposes a .22 calibre. Does that answer your question? ---
**Author:** ![mks57](https://avatars.discourse-cdn.com/v4/letter/m/b9bd4f/32.png) [@mks57](https://boards.straightdope.com/u/mks57)\ **Post date:** [May 14, 2007, 12:17am UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/56 "2007-05-14T00:17:49Z")
> [@](#): > > Was there a point at which M-16s and/or their ammo was re-designed to make the rounds tumble, making the tissue damage factor more equal to larger rounds? I seem to remember reading something to this effect. Not that I’m aware of. From what I’ve read, the bullets used in M16 ammunition, along with many other rifle bullets, are inherently unstable. The spin imparted by the rifling is the only thing keeping them stable. As soon as they hit something, and the spin is reduced below a certain level, the bullet starts to tumble. This is due to the aft location of the center of gravity in the bullet. It would prefer to fly base first. ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [May 14, 2007, 1:17am UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/57 "2007-05-14T01:17:59Z")
[QUOTE=Crafter\_Man] When you’re fighting someone, keep a close eye on his _hands_. Only hands can hurt you. [/QUOTE] This is a joke, right? ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [May 14, 2007, 1:27am UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/58 "2007-05-14T01:27:11Z")
[QUOTE=Crafter\_Man] Yep. Even if the bullet goes through the bad guy’s heart, he can still fight for up to 20 seconds. And this is where Hollywood has it all wrong… they always show the person falling down right away. This makes people \*think \* that they \*should \* fall when shot. [/QUOTE] Again, is this a joke? Do you really think people are out there getting shot and falling because they saw it on a movie? Does someone take a round in the chest and think “damn, what should I do? people fall down in the movies, I guess I’ll do that?” ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [May 14, 2007, 1:37am UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/59 "2007-05-14T01:37:33Z")
[QUOTE=Brain Wreck] Again, is this a joke? Do you really think people are out there getting shot and falling because they saw it on a movie? Does someone take a round in the chest and think “damn, what should I do? people fall down in the movies, I guess I’ll do that?” [/QUOTE] I’m not taking a position on this, but see the link **Crafter\_Man** posted upthread. Page 13 of the FBI report supports his statement. ---
**Author:** ![Dunderman](https://avatars.discourse-cdn.com/v4/letter/d/ecb155/32.png) [@Dunderman](https://boards.straightdope.com/u/Dunderman)\ **Post date:** [May 14, 2007, 5:29am UTC](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822/60 "2007-05-14T05:29:09Z")
[QUOTE=Blake] At this point in the thread I’m sure that someone has pointed out that most modern military rounds _are_ .22 calibre, right? The standard 5.5mm round is for all intents and purposes a .22 calibre. Does that answer your question? [/QUOTE] No, not really, but luckily other posts have. [Previous page](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822.md?page=2) [Next page](https://boards.straightdope.com/t/how-much-does-caliber-matter-in-self-defence/403822.md?page=4)