Firearms Tactical Institute



Work of the U.S. Government; not subject to copyright in the United States.




--------------------------------------------------------------------------------

Web Site Index and Navigation Center

U.S. Department of Justice

Handgun Wounding Factors and Effectiveness

Special Agent UREY W. PATRICK

FIREARMS TRAINING UNIT
FBI ACADEMY
QUANTICO, VIRGINIA

July 14, 1989

Forward

The selection of effective handgun ammunition for law enforcement is a
critical and complex issue. It is critical because of that which is at stake
when an officer is required to use his handgun to protect his own life or
that of another. It is complex because of the target, a human being, is
amazingly endurable and capable of sustaining phenomenal punishment while
persisting in a determined course of action. The issue is made even more
complex by the dearth of credible research and the wealth of uninformed
opinion regarding what is commonly referred to as "stopping power".

In reality, few people have conducted relevant research in this area, and
fewer still have produced credible information that is useful for law
enforcement agencies in making informed decisions.

This article brings together what is believed to be the most credible
information regarding wound ballistics. It cuts through the haze and
confusion, and provides common-sense, scientifically supportable, principles
by which the effectiveness of law enforcement ammunition may be measured. It
is written clearly and concisely. The content is credible and practical. The
information contained in this article is not offered as the final word on
wound ballistics. It is, however, an important contribution to what should be
an ongoing discussion of this most important of issues.

John C. Hall
Unit Chief
Firearms Training Unit



--------------------------------------------------------------------------------

Introduction

The handgun is the primary weapon in law enforcement. It is the one weapon
any officer or agent can be expected to have available whenever needed. Its
purpose is to apply deadly force to not only protect the life of the officer
and the lives of others, but to prevent serious physical harm to them as
well.1 When an officer shoots a subject, it is done with the explicit
intention of immediately incapacitating that subject in order to stop
whatever threat to life or physical safety is posed by the subject. Immediate
incapacitation is defined as the sudden2 physical or mental inability to pose
any further risk or injury to others.

The concept of immediate incapacitation is the only goal of any law
enforcement shooting and is the underlying rationale for decisions regarding
weapons, ammunition, calibers and training. While this concept is subject to
conflicting theories, widely held misconceptions, and varied opinions
generally distorted by personal experiences, it is critical to the analysis
and selection of weapons, ammunition and calibers for use by law enforcement
officers.3,4

Tactical Realities

Shot placement is an important, and often cited, consideration regarding the
suitability of weapons and ammunition. However, considerations of caliber are
equally important and cannot be ignored. For example, a bullet through the
central nervous system with any caliber of ammunition is likely to be
immediately incapacitating.5 Even a .22 rimfire penetrating the brain will
cause immediate incapacitation in most cases. Obviously, this does not mean
the law enforcement agency should issue .22 rimfires and train for head shots
as the primary target. The realities of shooting incidents prohibit such a
solution.

Few, if any, shooting incidents will present the officer with an opportunity
to take a careful, precisely aimed shot at the subject’s head. Rather,
shootings are characterized by their sudden, unexpected occurrence; by rapid
and unpredictable movement of both officer and adversary; by limited and
partial target opportunities; by poor light and unforeseen obstacles; and by
the life or death stress of sudden, close, personal violence. Training is
quite properly oriented towards "center of mass" shooting. That is to say,
the officer is trained to shoot at the center of whatever is presented for a
target. Proper shot placement is a hit in the center of that part of the
adversary which is presented, regardless of anatomy or angle.

A review of law enforcement shootings clearly suggests that regardless of the
number of rounds fired in a shooting, most of the time only one or two solid
torso hits on the adversary can be expected. This expectation is realistic
because of the nature of shooting incidents and the extreme difficulty of
shooting a handgun with precision under such dire conditions. The probability
of multiple hits with a handgun is not high. Experienced officers implicitly
recognize that fact, and when potential violence is reasonably anticipated,
their preparations are characterized by obtaining as many shoulder weapons as
possible. Since most shootings are not anticipated, the officer involved
cannot be prepared in advance with heavier armament. As a corollary tactical
principle, no law enforcement officer should ever plan to meet an expected
attack armed only with a handgun.

The handgun is the primary weapon for defense against unexpected attack.
Nevertheless, a majority of shootings occur in manners and circumstances in
which the officer either does not have any other weapon available, or cannot
get to it. The handgun must be relied upon, and must prevail. Given the idea
that one or two torso hits can be reasonably expected in a handgun shooting
incident, the ammunition used must maximize the likelihood of immediate
incapacitation.

Mechanics of Projectile Wounding

In order to predict the likelihood of incapacitation with any handgun round,
an understanding of the mechanics of wounding is necessary. There are four
components of projectile wounding.6 Not all of these components relate to
incapacitation, but each of them must be considered. They are:

(1) Penetration. The tissue through which the projectile passes, and which it
disrupts or destroys.

(2) Permanent Cavity. The volume of space once occupied by tissue that has
been destroyed by the passage of the projectile. This is a function of
penetration and the frontal area of the projectile. Quite simply, it is the
hole left by the passage of the bullet.

(3) Temporary Cavity. The expansion of the permanent cavity by stretching due
to the transfer of kinetic energy during the projectile’s passage.

(4) Fragmentation. Projectile pieces or secondary fragments of bone which are
impelled outward from the permanent cavity and may sever muscle tissues,
blood vessels, etc., apart from the permanent cavity.7,8 Fragmentation is not
necessarily present in every projectile wound. It may, or may not, occur and
can be considered a secondary effect.9

Projectiles incapacitate by damaging or destroying the central nervous
system, or by causing lethal blood loss. To the extent the wound components
cause or increase the effects of these two mechanisms, the likelihood of
incapacitation increases. Because of the impracticality of training for head
shots, this examination of handgun wounding relative to law enforcement use
is focused upon torso wounds and the probable results.

Mechanics of Handgun Wounding

All handgun wounds will combine the components of penetration, permanent
cavity, and temporary cavity to a greater or lesser degree. Fragmentation, on
the other hand, does not reliably occur in handgun wounds due to the
relatively low velocities of handgun bullets. Fragmentation occurs reliably
in high velocity projectile wounds (impact velocity in excess of 2000 feet
per second) inflicted by soft or hollow point bullets.10 In such a case, the
permanent cavity is stretched so far, and so fast, that tearing and rupturing
can occur in tissues surrounding the wound channel which were weakened by
fragmentation damage.11,12 It can significantly increase damage13 in rifle
bullet wounds.

Since the highest handgun velocities generally do not exceed 1400-1500 feet
per second (fps) at the muzzle, reliable fragmentation could only be achieved
by constructing a bullet so frangible as to eliminate any reasonable
penetration. Unfortunately, such a bullet will break up too fast to penetrate
to vital organs. The best example is the Glaser Safety Slug, a projectile
designed to break up on impact and generate a large but shallow temporary
cavity. Fackler, when asked to estimate the survival time of someone shot in
the front mid-abdomen with a Glaser slug, responded, "About three days, and
the cause of death would be peritonitis."14

In cases where some fragmentation has occurred in handgun wounds, the bullet
fragments are generally found within one centimeter of the permanent cavity.
"The velocity of pistol bullets, even of the new high-velocity loadings, is
insufficient to cause the shedding of lead fragments seen with rifle
bullets."15 It is obvious that any additional wounding effect caused by such
fragmentation in a handgun wound is inconsequential.

Of the remaining factors, temporary cavity is frequently, and grossly,
overrated as a wounding factor when analyzing wounds.16 Nevertheless,
historically it has been used in some cases as the primary means of assessing
the wounding effectiveness of bullets.

The most notable example is the Relative Incapacitation Index (RII) which
resulted from a study of handgun effectiveness sponsored by the Law
Enforcement Assistance Administration (LEAA). In this study, the assumption
was made that the greater the temporary cavity, the greater the wounding
effect of the round. This assumption was based on a prior assumption that the
tissue bounded by the temporary cavity was damaged or destroyed.17

In the LEAA study, virtually every handgun round available to law enforcement
was tested. The temporary cavity was measured, and the rounds were ranked
based on the results. The depth of penetration and the permanent cavity were
ignored. The result according to the RII is that a bullet which causes a
large but shallow temporary cavity is a better incapacitater than a bullet
which causes a smaller temporary cavity with deep penetration.

Such conclusions ignore the factors of penetration and permanent cavity.
Since vital organs are located deep within the body, it should be obvious
that to ignore penetration and permanent cavity is to ignore the only proven
means of damaging or disrupting vital organs.

Further, the temporary cavity is caused by the tissue being stretched away
from the permanent cavity, not being destroyed. By definition, a cavity is a
space18 in which nothing exists. A temporary cavity is only a temporary space
caused by tissue being pushed aside. That same space then disappears when the
tissue returns to its original configuration.

Frequently, forensic pathologists cannot distinguish the wound track caused
by a hollow point bullet (large temporary cavity) from that caused by a solid
bullet (very small temporary cavity). There may be no physical difference in
the wounds. If there is no fragmentation, remote damage due to temporary
cavitation may be minor even with high velocity rifle projectiles.19 Even
those who have espoused the significance of temporary cavity agree that it is
not a factor in handgun wounds:

"In the case of low-velocity missiles, e.g., pistol bullets, the bullet
produces a direct path of destruction with very little lateral extension
within the surrounding tissues. Only a small temporary cavity is produced. To
cause significant injuries to a structure, a pistol bullet must strike that
structure directly. The amount of kinetic energy lost in tissue by a pistol
bullet is insufficient to cause remote injuries produced by a high velocity
rifle bullet."20

The reason is that most tissue in the human target is elastic in nature.
Muscle, blood vessels, lung, bowels, all are capable of substantial
stretching with minimal damage. Studies have shown that the outward velocity
of the tissues in which the temporary cavity forms is no more than one tenth
of the velocity of the projectile.21 This is well within the elasticity
limits of tissue such as muscle, blood vessels, and lungs, Only inelastic
tissue like liver, or the extremely fragile tissues of the brain, would show
significant damage due to temporary cavitation.22

The tissue disruption caused by a handgun bullet is limited to two
mechanisms. The first, or crush mechanism is the hole the bullet makes
passing through the tissue. The second, or stretch mechanism is the temporary
cavity formed by the tissues being driven outward in a radial direction away
from the path of the bullet. Of the two, the crush mechanism, the result of
penetration and permanent cavity, is the only handgun wounding mechanism
which damages tissue.23 To cause significant injuries to a structure within
the body using a handgun, the bullet must penetrate the structure. Temporary
cavity has no reliable wounding effect in elastic body tissues. Temporary
cavitation is nothing more than a stretch of the tissues, generally no larger
than 10 times the bullet diameter (in handgun calibers), and elastic tissues
sustain little, if any, residual damage.24,25,26

The Human Target

With the exceptions of hits to the brain or upper spinal cord, the concept of
reliable and reproducible immediate incapacitation of the human target by
gunshot wounds to the torso is a myth.27 The human target is a complex and
durable one. A wide variety of psychological, physical, and physiological
factors exist, all of them pertinent to the probability of incapacitation.
However, except for the location of the wound and the amount of tissue
destroyed, none of the factors are within the control of the law enforcement
officer.

Physiologically, a determined adversary can be stopped reliably and
immediately only by a shot that disrupts the brain or upper spinal cord.
Failing a hit to the central nervous system, massive bleeding from holes in
the heart or major blood vessels of the torso causing circulatory collapse is
the only other way to force incapacitation upon an adversary, and this takes
time. For example, there is sufficient oxygen within the brain to support
full, voluntary action for 10-15 seconds after the heart has been destroyed.28

In fact, physiological factors may actually play a relatively minor role in
achieving rapid incapacitation. Barring central nervous system hits, there is
no physiological reason for an individual to be incapacitated by even a fatal
wound, until blood loss is sufficient to drop blood pressure and/or the brain
is deprived of oxygen. The effects of pain, which could contribute greatly to
incapacitation, are commonly delayed in the aftermath of serious injury such
as a gunshot wound. The body engages survival patterns, the well known "fight
or flight" syndrome. Pain is irrelevant to survival and is commonly
suppressed until some time later. In order to be a factor, pain must first be
perceived, and second must cause an emotional response. In many individuals,
pain is ignored even when perceived, or the response is anger and increased
resistance, not surrender.

Psychological factors are probably the most important relative to achieving
rapid incapacitation from a gunshot wound to the torso. Awareness of the
injury (often delayed by the suppression of pain); fear of injury, death,
blood, or pain; intimidation by the weapon or the act of being shot;
preconceived notions of what people do when they are shot; or the simple
desire to quit can all lead to rapid incapacitation even from minor wounds.
However, psychological factors are also the primary cause of incapacitation
failures.

The individual may be unaware of the wound and thus has no stimuli to force a
reaction. Strong will, survival instinct, or sheer emotion such as rage or
hate can keep a grievously injured individual fighting, as is common on the
battlefield and in the street. The effects of chemicals can be powerful
stimuli preventing incapacitation. Adrenaline alone can be sufficient to keep
a mortally wounded adversary functioning. Stimulants, anesthetics, pain
killers, or tranquilizers can all prevent incapacitation by suppressing pain,
awareness of the injury, or eliminating any concerns over the injury. Drugs
such as cocaine, PCP, and heroin are disassociative in nature. One of their
effects is that the individual "exists" outside of his body. He sees and
experiences what happens to his body, but as an outside observer who can be
unaffected by it yet continue to use the body as a tool for fighting or
resisting.

Psychological factors such as energy deposit, momentum transfer, size of
temporary cavity or calculations such as the RII are irrelevant or erroneous.
The impact of the bullet upon the body is no more than the recoil of the
weapon. The ratio of bullet mass to target mass is too extreme.

The often referred to "knock-down power" implies the ability of a bullet to
move its target. This is nothing more than momentum of the bullet. It is the
transfer of momentum that will cause a target to move in response to the blow
received. "Isaac Newton proved this to be the case mathematically in the 17th
Century, and Benjamin Robins verified it experimentally through the invention
and use of the ballistic pendulum to determine muzzle velocity by measurement
of the pendulum motion."29

Goddard amply proves the fallacy of "knock-down power" by calculating the
heights (and resultant velocities) from which a one pound weight and a ten
pound weight must be dropped to equal the momentum of 9mm and .45ACP
projectiles at muzzle velocities, respectively. The results are revealing. In
order to equal the impact of a 9mm bullet at its muzzle velocity, a one pound
weight must be dropped from a height of 5.96 feet, achieving a velocity of
19.6 fps. To equal the impact of a .45ACP bullet, the one pound weight needs
a velocity of 27.1 fps and must be dropped from a height of 11.4 feet. A ten
pound weight equals the impact of a 9mm bullet when dropped from a height of
0.72 inches (velocity attained is 1.96 fps), and equals the impact of a .45
when dropped from 1.37 inches (achieving a velocity of 2.71 fps).30

A bullet simply cannot knock a man down. If it had the energy to do so, then
equal energy would be applied against the shooter and he too would be knocked
down. This is simple physics, and has been known for hundreds of years.31 The
amount of energy deposited in the body by a bullet is approximately
equivalent to being hit with a baseball.32 Tissue damage is the only physical
link to incapacitation within the desired time frame, i.e., instantaneously.

The human target can be reliably incapacitated only by disrupting or
destroying the brain or upper spinal cord. Absent that, incapacitation is
subject to a host of variables, the most important of which are beyond the
control of the shooter. Incapacitation becomes an eventual event, not
necessarily an immediate one. If the psychological factors which can
contribute to incapacitation are present, even a minor wound can be
immediately incapacitating. If they are not present, incapacitation can be
significantly delayed even with major, unsurvivable wounds.

Field results are a collection of individualistic reactions on the part of
each person shot which can be analyzed and reported as percentages. However,
no individual responds as a percentage, but as an all or none phenomenon
which the officer cannot possibly predict, and which may provide misleading
data upon which to predict ammunition performance.

Ammunition Selection Criteria

The critical wounding components for handgun ammunition, in order of
importance, are penetration and permanent cavity.33 The bullet must penetrate
sufficiently to pass through vital organs and be able to do so from less than
optimal angles. For example, a shot from the side through an arm must
penetrate at least 10-12 inches to pass through the heart. A bullet fired
from the front through the abdomen must penetrate about 7 inches in a slender
adult just to reach the major blood vessels in the back of the abdominal
cavity. Penetration must be sufficiently deep to reach and pass through vital
organs, and the permanent cavity must be large enough to maximize tissue
destruction and consequent hemorrhaging.

Several design approaches have been made in handgun ammunition which are
intended to increase the wounding effectiveness of the bullet. Most notable
of these is the use of a hollow point bullet designed to expand on impact.

Expansion accomplishes several things. On the positive side, it increases the
frontal area of the bullet and thereby increases the amount of tissue
disintegrated in the bullet’s path. On the negative side, expansion limits
penetration. It can prevent the bullet from penetrating to vital organs,
especially if the projectile is of relatively light mass and the penetration
must be through several inches of fat, muscle, or clothing.34

Increased bullet mass will increase penetration. Increased velocity will
increase penetration but only until the bullet begins to deform, at which
point increased velocity decreases penetration. Permanent cavity can be
increased by the use of expanding bullets, and/or larger diameter bullets,
which have adequate penetration. However, in no case should selection of a
bullet be made where bullet expansion is necessary to achieve desired
performance.35 Handgun bullets expand in the human target only 60-70% of the
time at best. Damage to the hollow point by hitting bone, glass, or other
intervening obstacles can prevent expansion. Clothing fibers can wrap the
nose of the bullet in a cocoon like manner and prevent expansion.
Insufficient impact velocity caused by short barrels and/or longer range will
prevent expansion, as will simple manufacturing variations. Expansion must
never be the basis for bullet selection, but considered a bonus when, and if,
it occurs. Bullet selection should be determined based on penetration first,
and the unexpanded diameter of the bullet second, as that is all the shooter
can reliably expect.

It is essential to bear in mind that the single most critical factor remains
penetration. While penetration up to 18 inches is preferable, a handgun
bullet MUST reliably penetrate 12 inches of soft body tissue at a minimum,
regardless of whether it expands or not. If the bullet does not reliably
penetrate to these depths, it is not an effective bullet for law enforcement
use.36

Given adequate penetration, a larger diameter bullet will have an edge in
wounding effectiveness. It will damage a blood vessel the smaller projectile
barely misses. The larger permanent cavity may lead to faster blood loss.
Although such an edge clearly exists, its significance cannot be quantified.

An issue that must be addressed is the fear of over penetration widely
expressed on the part of law enforcement. The concern that a bullet would
pass through the body of a subject and injure an innocent bystander is
clearly exaggerated. Any review of law enforcement shootings will reveal that
the great majority of shots fired by officers do not hit any subjects at all.
It should be obvious that the relatively few shots that do hit a subject are
not somehow more dangerous to bystanders than the shots that miss the subject
entirely.

Also, a bullet that completely penetrates a subject will give up a great deal
of energy doing so. 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.37

Choosing a bullet because of relatively shallow penetration will seriously
compromise weapon effectiveness, and needlessly endanger the lives of the law
enforcement officers using it. No law enforcement officer has lost his life
because a bullet over penetrated his adversary, and virtually none have ever
been sued for hitting an innocent bystander through an adversary. On the
other hand, tragically large numbers of officers have been killed because
their bullets did not penetrate deeply enough.

The Allure of Shooting Incident Analyses

There is no valid, scientific analysis of actual shooting results in
existence, or being pursued to date. It is an unfortunate vacuum because a
wealth of data exists, and new data is being sadly generated every day. There
are some well publicized, so called analyses of shooting incidents being
promoted, however, they are greatly flawed. Conclusions are reached based on
samples so small that they are meaningless. The author of one, for example,
extols the virtues of his favorite cartridge because he has collected ten
cases of one shot stops with it.38 Preconceived notions are made the basic
assumptions on which shootings are categorized. Shooting incidents are
selectively added to the "data base" with no indication of how many may have
been passed over or why. There is no correlation between hits, results, and
the location of the hits upon vital organs.

It would be interesting to trace a life-sized anatomical drawing on the back
of a target, fire 20 rounds at the "center of mass" of the front, then count
how many of these optimal, center of mass hits actually struck the heart,
aorta, vena cava, or liver.39 It is rapid hemorrhage from these organs that
will best increase the likelihood of incapacitation. Yet nowhere in the
popular press extolling these studies of real shootings are we told what the
bullets hit.

These so called studies are further promoted as being somehow better and more
valid than the work being done by trained researchers, surgeons and forensic
labs. They disparage laboratory stuff, claiming that the "street" is the real
laboratory and their collection of results from the street is the real
measure of caliber effectiveness, as interpreted by them, of course. Yet
their data from the street is collected haphazardly, lacking scientific
method and controls, with no noticeable attempt to verify the less than
reliable accounts of the participants with actual investigative or forensic
reports. Cases are subjectively selected (how many are not included because
they do not fit the assumptions made?). The numbers of cases cited are
statistically meaningless, and the underlying assumptions upon which the
collection of information and its interpretation are based are themselves
based on myths such as knock-down power, energy transfer, hydrostatic shock,
or the temporary cavity methodology of flawed work such as RII.

Further, 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.

The problem, and the reason for seeking a better cartridge for
incapacitation, is that individual who is not predisposed to fall down. Or
the one who is simply unaware of having been shot by virtue of alcohol,
adrenaline, narcotics, or the simple fact that in most cases of grievous
injury the body suppresses pain for a period of time. Lacking pain, there may
be no physiological effect of being shot that can make one aware of the
wound. Thus the real problem: if such an individual is threatening one’s
life, how best to compel him to stop by shooting him?

The factors governing incapacitation of the human target are many, and
variable. The actual destruction caused by any small arms projectile is too
small in magnitude relative to the mass and complexity of the target. If a
bullet destroys about 2 ounces of tissue in its passage through the body,
that represents 0.07 of one percent of the mass of a 180 pound man. Unless
the tissue destroyed is located within the critical areas of the central
nervous system, it is physiologically insufficient to force incapacitation
upon the unwilling target. It may certainly prove to be lethal, but a body
count is no evidence of incapacitation. Probably more people in this country
have been killed by .22 rimfires than all other calibers combined, which,
based on body count, would compel the use of .22’s for self-defense. The
more important question, which is sadly seldom asked, is what did the
individual do when hit?

There is a problem in trying to assess calibers by small numbers of
shootings. For example, as has been done, if a number of shootings were
collected in which only one hit was attained and the percentage of one shot
stops was then calculated, it would appear to be a valid system. However, if
a large number of people are predisposed to fall down, the actual caliber and
bullet are irrelevant. What percentage of those stops were thus preordained
by the target? How many of those targets were not at all disposed to fall
down? How many multiple shot failures to stop occurred? What is the
definition of a stop? What did the successful bullets hit and what did the
unsuccessful bullets hit? How many failures were in the vital organs, and how
many were not? How many of the successes? What is the number of the sample?
How were the cases collected? What verifications were made to validate the
information? How can the verifications be checked by independent
investigation?

Because of the extreme number of variables within the human target, and
within shooting situations in general, even a hundred shootings is
statistically insignificant. If anything can happen, then anything will
happen, and it is just as likely to occur in your ten shootings as in ten
shootings spread over a thousand incidents. Large sample populations are
absolutely necessary.

Here is an example that illustrates how erroneous small samples can be. I
flipped a penny 20 times. It came up heads five times. A nickel flipped 20
times showed heads 8 times. A dime came up heads 10 times and a quarter 15
times. That means if heads is the desired result, a penny will give it to you
25% of the time, and nickel 40% of the time, a dime 50% of the time and a
quarter 75% of the time. If you want heads, flip a quarter. If you want
tails, flip a penny. But then I flipped the quarter another 20 times and it
showed heads 9 times - 45% of the time. Now this "study" would tell you that
perhaps a dime was better for flipping heads. The whole thing is obviously
wrong, but shows how small numbers lead to statistical lies. We know the odds
of getting a head or tail are 50%, and larger numbers tend to prove it.
Calculating the results for all 100 flips regardless of the coin used shows
heads came up 48% of the time.

The greater the number and complexity of the variables, the greater the
sample needed to give meaningful information, and a coin toss has only one
simple variable – it can land heads or it can land tails. The coin
population is not complicated by a predisposition to fall one way or the
other, by chemical stimuli, psychological factors, shot placement, bone or
obstructive obstacles, etc.; all of which require even larger numbers to
evidence real differences in effects.

Although no cartridge is certain to work all the time, surely some will work
more often than others, and any edge is desirable in one’s self defense.
This is simple logic. The incidence of failure to incapacitate will vary with
the severity of the wound inflicted.40 It is safe to assume that if a target
is always 100% destroyed, then incapacitation will also occur 100% of the
time. If 50% of the target is destroyed, incapacitation will occur less
reliably. Failure to incapacitate is rare in such a case, but it can happen,
and in fact has happened on the battlefield. Incapacitation is still less
rare if 25% of the target is destroyed. Now the magnitude of bullet
destruction is far less (less than 1% of the target) but the relationship is
unavoidable. The round which destroys 0.07% of the target will incapacitate
more often than the one which destroys 0.04%. However, only very large
numbers of shooting incidents will prove it. The difference may be only 10
out of a thousand, but that difference is an edge, and that edge should be on
the officer’s side because one of those ten may be the subject trying to
kill him.

To judge a caliber’s effectiveness, consider how many people hit with it
failed to fall down and look at where they were hit. Of the successes and
failures, analyze how many were hit in vital organs, rather than how many
were killed or not, and correlate that with an account of exactly what they
did when they were hit. Did they fall down, or did they run, fight, shoot,
hide, crawl, stare, shrug, give up and surrender? ONLY falling down is good.
All other reactions are failures to incapacitate, evidencing the ability to
act with volition, and thus able to choose to continue to try to inflict harm.

Those who disparage science and laboratory methods are either too short
sighted or too bound by preconceived (or perhaps proprietary) notions to see
the truth. The labs and scientists do not offer sure things. They offer a
means of indexing the damage done by a bullet, understanding of the mechanics
of damage caused by bullets and the actual effects on the body, and the basis
for making an informed choice based on objective criteria and significant
statistics.

The differences between bullets may be small, but science can give us the
means of identifying that difference. The result is the edge all of law
enforcement should be looking for. It is true that the streets are the
proving ground, but give me an idea of what you want to prove and I will give
you ten shootings from the street to prove it. That is both easy, and
irrelevant. If it can happen, it will happen.

Any shooting incident is a unique event, unconstrained by any natural law or
physical order to follow a predetermined sequence of events or end in
predetermined results. What is needed is an edge that makes the good result
more probable than the bad. Science will quantify the information needed to
make the choice to gain that edge. Large numbers (thousands or more) from the
street will provide the answer to the question "How much of an edge?".41 Even
if that edge is only 1%, it is not insignificant because the guy trying to
kill you could be in that 1%, and you won’t know it until it is too late.

Conclusions

Physiologically, no caliber or bullet is certain to incapacitate any
individual unless the brain is hit. Psychologically, some individuals can be
incapacitated by minor or small caliber wounds. Those individuals who are
stimulated by fear, adrenaline, drugs, alcohol, and/or sheer will and
survival determination may not be incapacitated even if mortally wounded.

The will to survive and to fight despite horrific damage to the body is
commonplace on the battlefield, and on the street. Barring a hit to the
brain, the only way to force incapacitation is to cause sufficient blood loss
that the subject can no longer function, and that takes time. Even if the
heart is instantly destroyed, there is sufficient oxygen in the brain to
support full and complete voluntary action for 10-15 seconds.

Kinetic energy does not wound. Temporary cavity does not wound. The much
discussed "shock" of bullet impact is a fable and "knock down" power is a
myth. The critical element is penetration. The bullet must pass through the
large, blood bearing organs and be of sufficient diameter to promote rapid
bleeding. Penetration less than 12 inches is too little, and, in the words of
two of the participants in the 1987 Wound Ballistics Workshop, "too little
penetration will get you killed." 42,43 Given desirable and reliable
penetration, the only way to increase bullet effectiveness is to increase the
severity of the wound by increasing the size of hole made by the bullet. Any
bullet which will not penetrate through vital organs from less than optimal
angles is not acceptable. Of those that will penetrate, the edge is always
with the bigger bullet.44



--------------------------------------------------------------------------------

References/Endnotes

FBI Deadly Force Policy.

Ideally, immediate incapacitation occurs instantaneously.

Fackler, M.L., MD: "What’s Wrong with the Wound Ballistics Literature, and
Why", Letterman Army Institute of Research, Presidio of San Francisco, CA,
Report No. 239, July, 1987.

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.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September, 1987. Conclusion of the Workshop.

Josselson, A., MD, Armed Forces Institute of Pathology, Walter Reed Army
Medical Center, Washington, D.C., lecture series to FBI National Academy
students, 1982-1983.

DiMaio, V.J.M.: Gunshot Wounds, Elsevier Science Publishing Company, New
York, NY, 1987: Chapter 3, Wound Ballistics: 41-49.

Fackler, M.L., Malinowski, J.A.: "The Wound Profile: A Visual Method for
Quantifying Gunshot Wound Components", Journal of Trauma 25, 522-529, 1985.

Fackler, M.L., MD: "Missile Caused Wounds", Letterman Army Institute of
Research, Presidio of San Francisco, CA, Report No. 231, April 1987.

Josselson, A., MD, Armed Forces Institute of Pathology, Walter Reed Army
Medical Center, Washington, D.C., lecture series to FBI National Academy
students, 1982-1983.

Fackler, M.L., MD: "Ballistic Injury", Annals of Emergency Medicine 15: 12
December 1986.

Fackler, M.L., Surinchak, J.S., Malinowski, J.A.; et.al.: "Bullet
Fragmentation: A Major Cause of Tissue Disruption", Journal of Trauma 24:
35-39, 1984.

Fragmenting rifle bullets in some of Fackler’s experiments have caused
damage 9 centimeters from the permanent cavity. Such remote damage is not
found in handgun wounds. Fackler stated at the Workshop that when a handgun
bullet does fragment the pieces typically are found within one centimeter of
the wound track.

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.

DiMaio, V.J.M.: Gunshot Wounds, Elsevier Science Publishing Company, New
York, NY 1987, page 47.

Lindsay, Douglas, MD: "The Idolatry of Velocity, or Lies, Damn Lies, and
Ballistics", Journal of Trauma 20: 1068-1069, 1980.

Bruchey, W.J., Frank, D.E.: Police Handgun Ammunition Incapacitation Effects,
National Institute of Justice Report 100-83. Washington, D.C., U.S.
Government Printing Office, 1984, Vol. 1: Evaluation.

Webster’s Ninth New Collegiate Dictionary, Merriam-Webster Inc., Springfield
MA, 1986: "An unfilled space within a mass."

Fackler, M.L., Surinchak, J.S., Malinowski, J.A.; et.al.: "Bullet
Fragmentation: A Major Cause of Tissue Disruption", Journal of Trauma 24:
35-39, 1984.

DiMaio, V.J.M.: Gunshot Wounds, Elsevier Science Publishing Company, New
York, NY 1987, page 42.

Fackler, M.L., Surinchak, J.S., Malinowski, J.A.; et.al.: "Bullet
Fragmentation: A Major Cause of Tissue Disruption", Journal of Trauma 24:
35-39, 1984.

Fackler, M.L., MD: "Ballistic Injury", Annals of Emergency Medicine 15: 12
December 1986.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September, 1987. Conclusion of the Workshop.

Fackler, M.L., MD: "Ballistic Injury", Annals of Emergency Medicine 15: 12
December 1986.

Fackler, M.L., Malinowski, J.A.: "The Wound Profile: A Visual Method for
Quantifying Gunshot Wound Components", Journal of Trauma 25: 522-529, 1985.

Lindsay, Douglas, MD: "The Idolatry of Velocity, or Lies, Damn Lies, and
Ballistics", Journal of Trauma 20: 1068-1069, 1980.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September 1987. Conclusion of the Workshop.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September 1987. Conclusion of the Workshop.

Goddard, Stanley: "Some Issues for Consideration in Choosing Between 9mm and
.45ACP Handguns", Battelle Labs, Ballistic Sciences, Ordnance Systems and
Technology Section, Columbus, OH, presented to the FBI Academy, 2/16/88,
pages 3-4.

Goddard, Stanley: "Some Issues for Consideration in Choosing Between 9mm and
.45ACP Handguns", Battelle Labs, Ballistic Sciences, Ordnance Systems and
Technology Section, Columbus, OH, presented to the FBI Academy, 2/16/88,
pages 3-4.

Newton, Sir Isaac, Principia Mathematica, 1687, in which are stated Newton’s
Laws of Motion. The Second Law of Motion states that a body will accelerate,
or change its speed, at a rate that is proportional to the force acting upon
it. In simpler terms, for every action there is an equal but opposite
reaction. The acceleration will of course be in inverse proportion to the
mass of the body. For example, the same force acting upon a body of twice the
mass will produce exactly half the acceleration.
Lindsay, Douglas, MD, presentation to the Wound Ballistics Workshop,
Quantico, VA, 1987.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September, 1987. Conclusion of the Workshop.
Jones, J.A.: Police Handgun Ammunition. Southwestern Institute of Forensic
Sciences at Dallas, 523D Medical Center Drive, Dallas, TX, 1985.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September, 1987. Conclusion of the Workshop.

Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA,
September 1987. Conclusion of the Workshop.

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.

He defines a one shot stop as one in which the subject dropped, gave up, or
did not run more than 10 feet.

This exercise was suggested by Dr. Martin L. Fackler, U.S. Army Wound
Ballistics Laboratory, Letterman Army Institute of Research, San Francisco,
California, as a way to demonstrate the problematical results of even the
best results sought in training, i.e., shots to the center of mass of a
target. It illustrates the very small actually critical areas within the
relatively vast mass of the human target.

Severity is a function of location, depth, and amount of tissue destroyed.

The numbers can be held down to reasonable limits by a scientific approach
that collects objective information from investigative and forensic sources
and sorts it by vital organs struck and target reactions to being hit. The
critical questions are what damage was done and what was the reaction of the
adversary.

Fackler, M.L., MD, presentation to the Wound Ballistics Workshop, Quantico,
VA, 1987.

Smith, O’Brien C., MD, presentation to the Wound Ballistics Workshop,
Quantico, VA, 1987.

Fackler, M.L., MD, presentation to the Wound Ballistics Workshop, Quantico,
VA, 1987.



Delivering you informative multimedia essays about the "battlefield
problem-solving" tactical aspects of armed self-defense.

Web Site Index and Navigation Center

Copyright ?1998 Firearms Tactical Institute. All Rights Reserved.
FirearmsTactical? Salus In Periculo, and logo are trademarks of Firearms
Tactical Institute.