Why private citizens really do need thirty round magazines

To say the citizen will never need thirty rounds for his own defense is clearly at odds with the evidence provided by real world shootings.


Most shots fired in gunfights miss. That is true even for skilled and experienced shooters. There are several reasons. Fear, excitement, adrenaline and confusion combine so that more misses are fired than hits. Unless you are a sociopath, you also have within you a bit of mental resistance to the idea of shooting someone else, even when it is plain that is what you need to do.  That resistance may surface later, after the shooting stops, as post shooting stress, but it is present at all times, and may contribute to missing your target. Some people have even felt a moment of hesitancy when aiming at human-outline silhouette targets at the shooting range.  Compounding these problems is that your assailants in a gunfight are likely to be in motion or taking cover behind whatever is available. Still another factor contributing to missing is that criminal activity often occurs at night and low light marksmanship is more challenging than popping away at targets on a sunny day at the range.

The tendency to miss in gunfights, even if you can shoot well on the range, is well documented in police and military studies. It is also evident in some news accounts of shootings. I will simply note a few sources in passing. Thomas J. Aveni's survey of police shootouts, "Officer-Involved Shootings: What We Didn’t Know Has Hurt Us" thoroughly reviews the problem of missing as it applies to police. The same thing has not been as well studied in regard to lawful self defense shootings by private citizens, but John Q. Public does not often shoot any better than the cops. The NRA's Armed Citizen accounts are not written to be case studies, and do not always document the number of shots fired versus the number of hits. The same is true of newspaper accounts. But where these facts are included you see once again that missing is very common.

The tendency to miss is so well established that it is assumed as the basis of other conclusions. This FBI paper questions overpenetration fears with regard to police bullets on the grounds that most shots fired by police at bad guys miss anyway.

The Department of Defense supports, in part, its use of the shotgun on the grounds that an assault rifle in combat is likely only to hit only one time in eleven while the shotgun's hit probability, within its range limitations, is twice as high. Twice as high is still more than five shots for each hit. These numbers may seem fantastically high until you consider that they are estimates from combat not the target range, and incorporate the difficulties already mentioned, of stress and of moving and hiding targets.

Police shootings might more nearly reflect the conditions the armed citizen faces. Here the numbers are not much more encouraging. The NYPD SOP-9 survey, cited by Aveni, records an average of a 15% ratio of shots the police fired to shots hitting the criminals, in the period 1990-2000. That works out to less than one hit for every six shots fired with pistols. Some other departments have claimed higher averages, but most reports do not upset the conclusion, generally accepted by those who review and analyze police shootings, that the cops are far more likely to miss than hit. To hit a criminal, the cops need multiple tries.

If we take all this into account, a thirty round magazine is none too big, particularly if you face multiple criminal assailants, as is common in home invasion scenarios. Unlike a policeman, the private citizen usually does not have a partner beside him or backup on the way. He needs plenty of firepower and may not have time to reload. His thirty round magazine has only three effective rounds in it if he manages a hit ratio of one in ten, six effective rounds if he hits one time in five. These are realistic ratios of hits to misses, as revealed in military and police experience. One in five would be darned good shooting, under some plausible scenarios, and better than predicted by the DOD or the NYPD, in the sources cited above. Some bad guys take more than one shot to stop them; let us factor that in as well. So then, three shots out of the magazine hit, or a very optimistic six, divided by two shots to stop each bad guy... your odds are none too good with thirty rounds. Want to give it a try with ten?

The argument that the private citizen does not need a thirty round magazine to hunt a deer is fatuous, for that is not the purpose or use of such magazines. The long magazines are mounted on rifles kept for defending  home and hearth. To say the citizen will never need thirty rounds for his own defense is clearly at odds with the evidence provided by real world shootings.