It is the intent of this article to educate you in what handgun ammunition is and is not capable of doing. Your ability to stop an assailant lies within you more so that the ammunition you use.  Whatever firearm and caliber you select, you must practice. Firing lots and lots of ammunition, even to hundreds upon hundreds of rounds until you can make accurate disabling hits on your target with some regularity. An accurate hit with a 90 grain  bullet fired from a 380 is better than a miss with a 230 grain bullet fired from a 45. The ability to hit you target (shot placement) is more important that having the latest 'wonder bullet' in your gun. I will say that while a 22 cal. hollow point bullet will kill, it does not make a good ‘stopper’ self defense round. It is too light in weight. If you had to get hit, ask yourself if you would rather get hit in the gut with 22 or a 45? A 45 cal on the other hand makes a good stopper because of the bullet weight and expansion factor. Not everyone can handle a 45. Where does that leave you? If you are like me, probably somewhere in the middle.

                    In every class someone always asks, “What caliber handgun do I need for personal defense”? “What type of ammunition does it take to stop the bad guy bent on doing you grave bodily harm? When faced with the threat of grave bodily harm or death by an assailant, we should have only one thing in mind. That is to survive the situation. If it becomes necessary to draw and shoot a weapon in self defense the immediate goal should be to stop the attack. The taking of a human life should never be the goal. Stopping an attack with one well placed shot would be idealistic. One shot stops are not the norm. Killing shots are those that hit the brain, brain stem, spinal cord or major artery. Stopping shots are those that hit with sufficient accuracy and force to persuade the attacker to cease his or her aggression. There are several things we need to consider when it comes to the ability of a handgun to ‘stop’ an assailant.

                   There are two prevalent and competing schools of thought on the ‘stopping power’ of handgun ammunition. The first school of thought is that smaller bullets and faster muzzle velocities achieve greater ‘stopping power’. The second school of though is that heavier bullets and slower muzzle velocities achieve greater ‘stopping power’.

                  The first school of thought is propounded in a book titled, “Handgun Stopping Power, The Definitive Study”.  By Evan Marshall and Ed Sanow. They have compiled a set of statistics based on results of actual one shot stop shootings in which one shot was fired into the torso of the attacker stopping the assault. The famed Miami FBI shoot-out played an important part of their study.  From these studies they have formulated percentage ratings for "one shot stops" for cartridges from .22 on up. The Marshall and Sanow numbers show a tendency for small and fast cartridges to do a little better than large and slow ones. The debate continues today as to source data, caliber/bullet weight combinations, and actual shootings they chose to exclude. Nevertheless, it's an interesting study.

                   The second school of thought is brought forth in a book written by Mr.Duncan MacPherson B.S. M.S. titled, “Bullet Penetration-Modeling the Dynamics and Incapacitation Resulting from Wound Trama” and propounded by Dr. Martin Fackler M.D. and others. The thrust of Mr. MacPherson's work is on getting the greatest efficiency out of a handgun.  He discusses accuracy, recoil, calibers. bullet types, bullet speeds and bullet weights as act and react in ballistics gelatin. He also takes into consideration, physiology and psychology of the person having been shot.

                    Caliber and type of bullet is a major consideration. There is a lot of misinformation available in the gun magazines and on the internet as to which caliber/bullet combination  is the ‘best’ when it comes to stopping violent criminal aggression. Always remember that the gun rags depend on advertising to make a profit. Have you ever seen a bad review of ANY product in a gun mag.? There are several things to consider when deciding which caliber/bullet to use. Consider the ability of the ammunition  to penetrate sufficiently and your ability to handle handgun/caliber with complete control. That is to say, if you cannot control the handgun you will not be able to fire successive shots with any accuracy. If you are afraid to shoot because of recoil you cannot handle, then your handgun/caliber becomes useless.

                   Self-defense ammunition must be able to penetrate the human body to a depth so as to reach vital organs and or the spinal cord and bullet weight must be heavy enough so as to have ‘shocking value’ to persuade an assailant to either fall down or give up the fight. Notice I said, ‘fall down’. Handgun ammunition does not have enough energy to ‘knock’ a person down. More on this later. The stopping power of handgun ammunition hinges on several things:

                    First ..... is damage to the central nervous system such as shots to the brain, brain stem or spinal cord which usually cause immediate incapacitation. A hit to the brain would incapacitate instantly. How wide is the spinal cord? Answer, no very.  As an afterthought, what are the chances of you hitting an assailant’s brain or spinal cord? Slim to none.

                    Second .....by hemorrhage or blood loss which causes a severe drop in blood pressure and a lack of oxygen to the brain. The major arteries which carry blood to the whole body are located along the spine. It is accepted that even when hit in the heart or liver, a determined assailant can still function for 10 seconds or so. Killing shots are not necessarily stopping shots when it comes to the assailant doing you harm. An assailant can do a lot of harm to you, maybe even kill you in a few short seconds. We know the approximate location of these organs, however, we should not make them a specific target. We teach to place your hits in the 'center mass' area.

                   Third .....by the effects of what I’ll call the ‘shock value’ of the ammunition. The shock value of ammunition is the cumulative effect of what the shock produces, both physically and. psychologically. The physical effects of the shock of a bullet passing through tissue can be measured by its permanent wound channel and its temporary wound channel. A bullet must disrupt vital tissue to be effective. Tissue damage and disruption are caused by the diameter, weight, velocity and expansion factor of the bullet.  I’ll just call it the hole the bullet leaves on its path through tissue. Human tissue can take a lot of abuse before it is destroyed. Most tissue in the human body has a lot of ‘give’ to it. That is to say, it is elastic. Muscle tissue, blood vessels, lung, bowels, all are subject to stretching without causing much damage. Tissue damaged in this way is considered to be a temporary wound channel. Maximum tissue destruction increases the chances for destruction of vital nerves and or blood vessels or arteries. The liver and the brain, are not elastic and would be dramatically damaged due to a wound channel. A hit to the liver or heart or major artery would cause excessive bleeding. The assailant would have a few seconds to function normally before blood loss would cause a severe drop in blood pressure and a lack of oxygen to the brain.

                    The psychological effect of a bullet passing through tissue is a little more complicated. Notice I said psychological not physical. Just how important is it? Man is conditioned by TV and the movies to fall down when hit. How many times have you seen a person on TV get hit and be bowled over backwards? It looks good on TV but it is not reality. Often times you will not know if you hit your target or not. On the other hand, if you are mentally conditioned to fall down when struck by a bullet……you will. This is not a result of ‘knockdown power’ but mental conditioning. It has also been called emotional fainting¹. It is least likely to occur in people who are high on drugs, mentally disturbed or those who are determined to do as much harm to you as they can before being stopped. It is more likely to occur in someone who has no idea that they will be, or have been shot. The greater the ‘shock’ the greater the chances of the assailant falling down.  This applies to the victim as well as the assailant. Have you ever given any thought that in a violent confrontation you might be shot or stabbed? This is why we stress in class to never give up the fight. You must decide right now that you will not give up, ever. You must refuse to become a statistic even when shot or stabbed yourself. You must not faint at the sight of blood either yours or your assailant’s. That is a very sobering thought. How would you react? No one can answer that question until it happens to them.  Conversely, what about the bad guy? How is he conditioned? Fact is you don’t know. Will he fall down and give up when hit in a less that lethal spot? You certainly hope so! What if he doesn’t?  If you have taken our classes you have learned to shoot and keep shooting until the threat stops, how many ever shots that takes.

                    Do you remember physics class in high school? Newton's Third Law of Motion states that every action creates an equal but opposite reaction. The energy a handgun/bullet produces in one direction can never be more than the energy occurring in the opposite direction. If there is enough energy to ‘knock down’ an assailant then it follows that there is enough energy (in the opposite direction) to also knock down the one doing the shooting.  What does this mean in layman’s terms? The muzzle energy of handgun ammunition of itself is not a reliable one shot stopper, however, it is beneficial to have as much muzzle energy (knock down power) as possible. The ‘shock’ of being shot can cause one who has been conditioned to fall to actually fall, or hopefully give up the fight, however, don’t bet your life on it.

                        What about pain you ask? Will pain in and of itself stop an assailant?  Don’t bet your life on this either. Pain must be ‘felt’ before it can become a factor in stopping an assailant. People high on drugs can be impervious to pain. Cocaine, PCP, and heroin are examples of such drugs. Tranquilizers and anesthetics are also to a degree. An adrenalin rush itself can be sufficient to suppress pain also. While in Viet Nam I witnessed a lot of amazing things. The Viet Cong‘s ability to fight with their guts shot out or limbs half off as though nothing had happened to them was amazing. Why? They weren’t hit in the central nervous system or a major artery and they didn’t feel any pain. Our outfit believed that their commanders would dope them up before a fight for that very reason. Pain must cause an emotional reaction to become a factor. Some folks are more tolerant of pain than others. Some folks have the ability to ignore pain while others fall to pieces with the slightest pain. Pain can be factor in stopping an assailant but it is not something you can depend on. Lets say you don’t achieve a hit to a ‘vital’ organ or spine. Lets say you have only achieved torso hits to the abdomen. The previous mental conditioning of the assailant becomes the important factor. Trouble is, we don’t know the assailants mental conditioning. He or she could ‘fall down’ and give up or he or she could grin and continue the aggression. It follows then that hits to the lower torso or extremities (unless a nerve or major artery is hit) are very unreliable ‘stoppers’.

                     Center mass hits provide the greatest odds of stopping an assailant. When I say ‘center’, I mean center. You can see by the illustrations above that the spinal cord and major arteries are just that, in the center. Extremity hits are less effective ‘stoppers’, however, they can produce stops if the wound channel is severe enough to cause major tissue damage and the assailant is psychologically conditioned to fall and or give up when hit.

                    What caliber/bullet combination is sufficient to accomplish all of this? There are priorities to consider when selecting personal defense ammunition. In order of importance they are the ability of ammunition to penetrate to a depth that will affect vital organs, to include brain, heart, liver and spinal cord. If the assailant was standing sideways to you it would take approximately 12” of penetration to pass through an arm and hit the heart. An arm obstructs about 20 percent of the torso when it is outstretched and pointing a gun, and you're shooting at the bad guy from a front angle. Likewise an arm can obstruct 50 percent or more of the torso when you engage a bad guy with gunfire from a side angle. Therefore there’s a good chance that your bullet could hit an arm, and that’s part of the rationale behind the 12-inch minimum penetration performance guideline.² The ammunition must be able to create a permanent wound channel as large as possible in order to maximize damage to nerves or arteries.  

                    Hollow point ammunition is the accepted type used for personal defense. Hollow point ammunition is designed to expand on contact. This is desirable as it increases the size of the wound channel. The downside to hollow point ammunition is that due to increased expansion it creates more friction thus limiting penetration. To counteract lack of penetration, bullet mass must be increased (larger caliber and/or heavier weight). Increased speed of the bullet or velocity will increase penetration but only until the bullet begins to expand, at which point increased velocity decreases penetration. The most critical factor is penetration. A handgun bullet must be able to penetrate clothing and soft tissue to a depth of 12 inches in order to hit vital organs regardless of whether it expands or not. Bullet expansion is secondary to penetration.

                    What about over penetration? Fact #1: Any energy a bullet has after passing through tissue is wasted energy. The bullet can no longer do damage to the assailant if it is no longer present. The skin on the exit side of the body is tough and flexible. Experiments have shown that it has the same resistance to bullet passage as approximately four inches of muscle tissue.³    Fact #2: You are responsible for every round that leaves your handgun, therefore, over penetration is an issue you must come to terms with before it becomes a problem for you. Is there a danger of hitting a bystander with a bullet that over penetrates? You betcha! A bullet that completely penetrates a subject will give up a great deal of energy doing so, however, it may still have enough energy and velocity to do much damage or even kill someone you did not intend to hit. If this happens you are liable for any damage that may occur.  To be sure, there is always a danger of over penetration, however, the majority of the energy of the bullet is already expended.  The greater danger of collateral damage occurs when you miss your target completely, therefore, a good solid hit is more important than which caliber you choose.

REFERENCES:

1. Fackler, Martin L., M.D.: "Incapacitation Time." Wound Ballistics Review 4(1), Spring 1999; 4-8.

2.Tactical Briefs (Volume 2, Number 3) March 1999

3. Fackler, M.L., M.D., Director, Wound Ballistics Laboratory, Letterman Army Institute of Research, Presidio of San Francisco, CA, letter: "Bullet Performance Misconceptions", International Defense Review 3; 369-370, 1987.

                    It is not the intent of this article to tell you which caliber/ammunition combination to use for personal defense, however, a good rule of thumb is to ask what your local law enforcement agencies are using.  They have studied, tested and tried lots of ammo.  You must educate your self and take some responsibility yourself. You must know your own abilities and limitations when it comes to handling a firearm.  Using a handgun for personal defense is an awesome responsibility. You are referred to the various manufacturers of handgun ammunition for their specifications.