CvSU Vision
The
premier
university in historic
Cavite recognized for
excellence in the
development
of
globally competitive
and morally upright
individuals.
Republic of the Philippines
CAVITE STATE UNIVERSITY
Don Severino de las Alas Campus
Indang, Cavite
CvSU Mission
Cavite State University shall
provide excellent, equitable and
relevant
educational
opportunities in the arts, science
and technology through quality
instruction
and
relevant
research
and
development
activities.
It shall produce professional,
skilled and morally upright
individuals
for
global
competitiveness.
COLLEGE OF CRIMINAL JUSTICE
Department of Criminology
FOSC 23 – FORENSIC BALLISTICS
LEARNING MODULES PART 2
Prepared by: Darlito Bernard G. Delizo, PhD
MODULE 10 - SHOTGUN
Most of the topics included in the text of this Module were copied and pasted from
https://www.newworldencyclopedia.org/entry/Shotgun.
A. Shotgun is a shoulder gun that fires a cartridge that contains a powder charge and a load of
metal pellets, called shot. The shot spreads over a wide area. This makes it easier to hit a
moving target with a shotgun than with the single bullet from a rifle or a pistol. The shotgun
is chiefly a hunting gun.
A shotgun is a firearm, usually with a smooth bore (as opposed to a rifled bore), and
designed to fire a charge of spherical pellets, usually called a "shot." A shotgun usually has a
buttstock and is carried and fired by one person. Waterfowl and other birds are nearly always
hunted using shotguns, so a shotgun has sometimes been called a fowling piece. It is also
called a scattergun because the charge of pellets fired from its barrel forms a pattern that
spreads out, or scatters, into an ever-enlarging circle the farther it moves from the muzzle of
the firearm.
B. EARLY HISTORY OF SHOTGUN
1. The first shotgun, developed in 1537, was loaded with small shot instead of one round
ball. In 1831, Augustus Demondion patented a cartridge that held small shot.
2. The first recorded use of the term shotgun was in 1776, in Kentucky, as part of the
"frontier language of the West" by James Fenimore Cooper. With the adoption of guns of
smaller bores with rifled barrels, especially the Pennsylvania rifle about 1725 and later, the
shotgun, as a smoothbore gun intended to fire a charge of shot instead of a single bullet,
began to emerge as a separate entity about the beginning of the nineteenth century. The
side-by-side double-barreled shotgun has changed little since about 1875.
3. Cavalry units on both sides of the American Civil War used black powder muzzle-loading
shotguns. American cavalry used the shotgun extensively during the Indian
Wars throughout the latter half of the nineteenth century. Shotguns were also favored by
citizen militias and similar groups. Shotguns were used in the defense of The Alamo
during Texas' War of Independence with Mexico.
4. Except for cavalry units, the shotgun saw less and less military use throughout the
nineteenth century. It remained popular with guards and lawmen, however, and the
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shotgun became one of many symbols of the American Old West. The famous lawman,
Cody Lyons, killed two men with a shotgun; his friend Doc Holliday's only confirmed kill
was with a shotgun.
5. Both these men used the short-barreled coach gun shotgun, favored by private strongbox
guards on stages and trains. These guards rode the coach sitting next to the driver, with the
weapon loaded with buckshot for defense against bandits. Passenger carriages carrying a
strongbox usually had at least one such private guard armed with a shotgun. This has
survived in American slang; the term "riding shotgun" is used for the passenger who sits in
the front passenger seat.
6. Daniel Myron LeFever is credited with the invention of the hammerless shotgun in 1878,
while working for Barber & LeFever in Syracuse, N.Y. This gun was cocked with external
cocking levers on the side of the breech. He formed his own company, The LeFever Arms
Co., in 1880, and went on to patent the first truly automatic hammerless shotgun in 1883.
This gun automatically cocked itself when the breech was closed. He also invented
automatic ejectors, to throw out the empty case after firing.
7. John Moses Browning - Famed gun designer John Browning made numerous shotgun
innovations and revolutionized shotgun design while working for Winchester Firearms. In
1887, Browning introduced the Winchester Model 1887 Lever Action Repeating Shotgun,
which loaded a fresh cartridge from its internal magazine by the operation of the action
lever. Before this time, most shotguns were the break open type. That was overshadowed
by two further Browning innovations at the end of the nineteenth century. In 1893, he
produced the Model 1893 Pump Action Shotgun, introducing that now familiar shotgun
type to the market. Then in 1900, he patented the Browning Auto-5, the world's first semiautomatic shotgun; it remained in production until 1998.
C. TYPES OF SHOTGUNS
1. Single shot type or non-repeater - only one shell can be loaded in the gun and it has to be
reloaded before it can be fired again. Single shot shotguns are usually break-open designs,
meaning that the barrel swings, on a hinge, away from the breech for loading and
unloading.
2. Repeater types or multiple-shot, shotguns - at least two shells can be loaded in the gun at a
time, and thus at least two shots can be fired before the gun needs to be reloaded.
a. Double barrel – It is also a break-open design in which there are two barrels built
together next to one another on the same shotgun frame, and each barrel is loaded with
a shell. After the first is fired, the second can be fired either by pulling the trigger a
second time (on single trigger guns) or by pulling the second trigger (on double trigger
guns). Two types of double barrel: side by side if the two barrels are next to each other
horizontally, or the over under if the two barrels are mounted one over the other
vertically. The side by side is the older design. Early side by side double barrel
shotguns had exposed hammers that had to be manually cocked before firing, but
today's guns use a hammerless design.
b. Pump action (also known as a slide action or, sometimes, a trombone action) gun several shells can be loaded at a time into a magazine built into the gun, and the action
is operated by hand-pulling the forestock back and then forward. This ejects the spent
shell and puts a fresh shell from the magazine into the chamber so that the gun can be
fired again by pulling the trigger.
c. Autoloader—sometimes mistakenly called an "automatic." However, a true automatic
is a machine gun, in which the gun continues firing as long as the trigger is held and
there is fresh ammunition being fed into the gun. In an autoloader, the gun mechanism
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uses either the gas from the firing (known as gas operated) or the recoil from the firing
(recoil operated) to work the mechanism, ejecting the spent shell and loading a fresh
one from the magazine into the chamber, readying the gun for firing again when the
trigger is pulled again.
d. Lever action shotgun – it looks and works like the lever operated Winchester rifles
often seen in Western movies. Today this shotgun type is quite rare, and is never seen
in organized matches in the shotgun sports.
e. Bolt action shotgun – it has a bolt handle. After the first shot, the bolt is manually
turned open and pulled back, ejecting the spent shell, and then shoved forward, picking
up and chambering a fresh shell, and closed again.
3. Specialized shotguns
a. Specialized police and defensive shotguns are called Riot shotguns or Riot guns. The
introduction of rubber bullets and bean bag rounds ended the practice of using shot for
the most part, but riot shotguns are still used to fire a variety of less than lethal rounds
for riot control.
b. A sawed-off shotgun is one whose barrel has been shortened, leaving it more
maneuverable, easier to use at short range and more readily concealed. Most countries
have legal minimum lengths for shotgun barrels.
c. Coach Guns, usually of side-by-side double barrel design, are similar to sawed-off
shotguns, except they are manufactured with an 18" barrel and are legal for civilian
ownership in some jurisdictions. Coach guns are also commonly associated with the
American Old West.
d. A backpacker shotgun has a short barrel (often less than 15" barrel length) and either
a full-size stock or pistol grip, depending on legislation in intended markets. These
weapons are typically break-action .410, single-barrel designs with no magazine and no
automatic ejection capability. Backpacker shotguns are popular as survival weapons.
Other examples include a variety of shotgun barrel (usually a .410) over a rifle barrel
combinations, marketed as a "survival" device. Generally, there is one manually-cocked
external hammer and an external selection lever to select which caliber of cartridge to
fire.
e. Shotgun/rifle combination guns with three or even four barrels, commonly known
as drillings, are available from a number of European makers—they are almost
unknown in America. These provided flexibility, enabling the hunter to effectively
shoot at flushing birds or more distant mammals while carrying only one gun.
D. SHOTGUN GAUGES AND CALIBERS - Shotgun sizes are usually expressed in terms
of gauge. Gauge was originally determined by the number of perfectly round lead balls of
equal size required to make a pound. Thus, if 12 round lead balls made a pound, the diameter
of those balls equaled the diameter of a 12 gauge shotgun, and if it took 20 balls to make a
pound, the diameter of one of those was the diameter of a 20 gauge shotgun. The one
exception to "gauge" as the term of shotgun bore size is the .410 shotgun; this designation,
.410 of an inch, is the actual bore size of this shotgun. Today shotgun bore sizes are
standardized:
1. 10 gauge = 0.775 inch
2. 12 gauge = 0.729 inch
3. 16 gauge = 0.662 inch
4. 20 gauge = 0.615 inch
5. 28 gauge = 0.550 inch
6. .410 bore = 0.410 inch
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The 12 gauge is by far most common, followed by the 20 gauge. Ten gauge is sometimes
used for large waterfowl hunting. In the past, the 16 gauge was very common and preferred
by many shotgun shooters, but it is less commonly used today, and ammunition for it is also
harder to find than 12 or 20 gauge. In the past there were additional gauges, such as 4, 8, 14,
24, and 32 gauges. Those are now obsolete, and ammunition for them is usually unavailable.
E. SHOTGUN CARTRIDGES consist of a plastic or paper tube with a brass or steel case at
one end. They contain lead or steel shot instead of bullets. Ammunition for shotguns is
usually called a shotgun shell, or shot shell, or simply shell. The term cartridge is used
for rifle ammunition, but not for shotgun shells. A shotgun shell consists of five parts:
1. The outer shell, or hull, or case, with its (usually) brass or steel base; the outer shell today
is usually made of plastic, although thick cardboard-like paper was used in the past and
some paper shot shells are still made
2. The primer, which is a small percussion cap set in a hole in the center of the base of the
shell; this primer is struck by the firing pin of the shotgun when fired and ignites the
gunpowder
3. The gunpowder itself; this is placed inside the shell case at the bottom, just above the
primer
4. A wad, or wads, between the powder and the shot; today, wads are usually made of plastic
and are one-piece; in the past wads were often of paper or cardboard or kapok or similar
material and there were numerous such pieces, often of different materials and somewhat
different shape, within a single shot shell
5. The shot itself, resting atop the wad and just under the mouth of the shell
Today's plastic shot shells have a crimped mouth, but paper shot shells usually had a top
wad over the shot with a rolled crimp on the mouth of the shell body, holding the top wad in
place. Slugs have the front of the slug visible; it is held in place in the loaded shell with a
rolled crimp even if the body of the shell is made of plastic.
Shotgun shells are loaded to different lengths. The most common length, except for 10
gauge and .410 bore, is 2 ¾ inches, but some, especially for 20, 12, and 10 gauges are longer,
and .410 loads are either 3 inches or 2 ½ inches long—these lengths are the length of the hull
or case after the shell is fired. The length of load that can be used depends on the chamber of
the shotgun in which the load is to be fired—the chamber must be at least as long as the
longest load to be used. Different shotgun loads contain different amounts and/or sizes or
types of shot, and are loaded to achieve somewhat different muzzle velocities.
F. SHOTGUN PROJECTILES. Most shotguns loads contain ball shot, usually known
as pellets. In the past, the pellets were almost always made of lead. But non-toxic loads are
required by Federal law in the United States for waterfowl hunting, so lead pellets in shotgun
loads have been partially replaced by bismuth, steel, tungsten-iron, tungsten-nickel-iron, or
other substances—such non-lead shot is required for waterfowl shooting, and usually
permissible elsewhere. Lead shot is still most commonly used for non-waterfowl hunting and
for shotgun sports.
G. SHOT WADS. At a distance of 5-8 yards or more from the place of firing in the
approximate direction of fire, one can sometimes find wads.
H. SHOTGUN PROJECTILES. Shot is often termed either birdshot or buckshot, depending
on the shot size.
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1. Birdshot pellets have a diameter smaller than 0.20 inches (5 mm) and buckshot is larger
than that. Pellet size is indicated by a number, for bird shot this ranges from the smallest
#12 (0.05 in) to #2 (0.15 in) and then BB (0.18 in). Bird shot pellets are small enough that
they can be measured into the cartridge by weight, and just poured in.
2. For buckshot, the numbers usually start at 4 (0.24 in) and go down to 1, 0, 00, 000, and
finally 0000 (.38 in). Trap, skeet, and sporting clays shooting use shot of #7½ or smaller.
Large bird and waterfowl hunters usually use shot of #6 or larger. Buckshot is usually used
for larger game hunting, such as deer. buckshot pellets are so large they won't all fit unless
they're stacked inside the cartridge one by one in a certain particular geometric
arrangement.
3. Buckshot is legal or even legally required for this use in some jurisdictions, but banned in
others.
4. In addition, there are shotgun loads that contain a single shaped lead projectile, called
a shotgun slug, or just a slug. A shotgun slug is a single heavy projectile, and shotgun
slugs often have finned rifling designed to spin the bullet and stabilize it in order to
improve its accuracy. Some shotguns are fitted with rifled barrels (these barrels are usually
interchangeable with a smoothbore barrel on the same gun) that are designed to be used
with a special type of shotgun slug that is encased in a plastic ring holder (sabot) designed
to peel away after it exits the barrel, leaving the slug now spinning (and thus stabilized)
after passing through the rifled barrel. These shotguns, although they have rifled barrels,
still use a shotgun-style shell instead of a rifle cartridge and may in fact still fire regular
multi-pellet shotgun shells, but the rifling in the barrel will affect the shot pattern.
5. Chilled Shot – shotgun pellets made from lead especially hardened by the addition of a
slight amount of antimony.
I. SHOTS BALLISTICS - deals with the attributes and properties of shots and pellets. When a
shotshell is fired from a shotgun, the pellets leave the barrel and begin to spread or scatter.
The farther the pellets travel, the greater the spread of shot. Shotgun barrels have a choke to
control the spread or shot pattern.
1. As the shot leaves the barrel it begins to disperse in the air. The resulting cloud of pellets
is known as the shot pattern; this pattern spreads out into an ever-widening circle as it
travels away from the muzzle of the shotgun. Patterns are usually measured by firing at a
30 inch (76cm) diameter circle on a larger sheet of paper placed at varying distances. The
hits inside the circle are counted, and compared to the total number of pellets, and the
density of the pattern inside the circle is examined. An "ideal" pattern would have no
voids; any region where a target silhouette will fit and not cover 3 or more holes is
considered a potential problem.
2. A constriction in the end of the barrel known as the choke is used to tailor the pattern for
different purposes. Choke also refers to the degree of narrowing at the muzzle end of the
shotgun barrel Chokes may either be formed as part of the barrel at the time of
manufacture, by squeezing the end of the bore down over a mandrel, or by threading the
barrel and screwing in an interchangeable choke tube. The choke usually tapers smoothly
from the bore diameter down to the choke diameter. The use of interchangeable chokes
has made it easy to tune the performance of a given combination of shotgun and shot shell
to achieve the desired performance.
3. The choke should be tailored to the range and size of the targets. The use of too much
choke and a small pattern increases the difficulty of hitting the target; the use of too little
choke produces large patterns with insufficient pellet density to reliably break targets or
kill game. "Cylinder barrels" have no constriction.
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4. The choke acts like the nozzle of a garden hose. As the nozzle is tightened, water shoots
out in a long, narrow stream, similar to the full choke on a shotgun. As the nozzle is
opened, similar to the cylinder choke on a shotgun, water shoots out in a wider spray.
Your distance from the target determines the choke you need. The choke does not alter the
shotgun’s power—it just controls how tight or spread out the shot pattern will be at a
specific distance.
J. SHOT PATTERN - The spread of shot pellets after they hit a non-moving target.
K. TYPES OF SHOTGUN BARRELS
1. Cylinder Bore - diameter of a barrel of a shotgun is the same throughout the bore, it is
called true cylinder.
2. Choked - diameter near the muzzle end is slightly smaller than the diameter of the bore of
the rest of the barrel. Types of choked barrel a. Chokes are classified as: Full – if reduced by one mm; half if reduced by one-half mm;
quarter if reduced by ¼ mm; and improved cylinder if reduced by about 1/10 mm.
b. Chokes are also classified as:
1) Cylinder choke is an unconstricted barrel which produces most open pattern suitable
for shortest ranges. At longer range, pattern is too thin to ensure hits. The shot string
spreads quickly.
2) Improved Cylinder choke has a slight constriction which produces an even more
open pattern suitable for short ranges and for longer ranges, the shot pattern is too
thin to ensure hits. It allows the shot string to spread fairly quickly. This is a good
choice for quail, rabbits, and other upland game at relatively close ranges.
3) Modified choke has moderate constriction which produces more open pattern, which
is suitable for medium ranges and for upland hunting. The pellets stay together
longer, making the shot string denser and more useful at longer ranges. This choke is
used often when dove hunting and when using steel shot to hunt for ducks or geese.
There is also an Improved Modified choke that is slightly tighter than Modified.
4) Full choke has tight constriction which produces a tight pattern and for longer
ranges. Pattern is too dense and small for hunting at close range. The shot holds
together even longer, making this choke good for squirrels, turkey, and other game
shot at 40-yard and longer ranges. Turkey hunters sometimes use Extra Full or
Turkey choke for even denser patterns at long range.
L. SHOTGUN WOUND. In shotgun fire, the pellets penetrate and usually lodged inside the
body and a tendency for a wider dispersion of pellets at a certain distance except in contact
and near contact fires. Characteristics of the shotgun wound of entrance:
1. Contact fire - irregular with bursting of the affected tissues due to explosion of the
heated and expanded with accompanying flame causing burning of the skin and the
tissues. There is singeing of the hair; presence of wads and particles of gunpowder
inside the wound of entrance.
2. Near shot up to six inches distance. There is marked laceration of the skin
and destruction of tissues due to the pressure of explosion. The burning on the surface of
the skin and particles of gunpowder are present inside and around the wound of entrance.
There is singeing of the hair as well as pieces of wads inside and outside the wound of
entrance.
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3. Distance about one yard. The pellets penetrate the tissues as one mass making the
wound with irregular edge of the wound of entrance. There will also be blackening of
tissues with slight burning, singeing of the hair or gunpowder tattooing.
4. Distance about two to three yards. The wound of entrance has a big central hole with
ragged edges and a few stray wounds of entrance around the central hole. At this
distance, there will be no more blackening or burning of the skin, gunpowder tattooing,
singeing of the hair and pieces of wads or near the wound of entrance.
5. Distance of four yards. A small group of pellets may penetrate the tissues producing a
central core, although plenty of pellets in a wider dispersion may produced separate
wound of entrance. The pellets dispersed about one and a half the distance in yards in
non-choked barrel while in full-choked bore the dispersion is one half less but there is a
wider dispersion in short barrel shotgun.
Points to consider in the reporting of gunshot and shotgun injuries:
1. Detailed description of the gunshot and shotgun wound
2. Location of wound in the body
3. Measurement of the wound as to diameter and depth
4. Number of wound of entrance and exit
5. Direction and length of the bullet tract
6. Organs or tissues involved
7. Location of the slug if lodged in the body
8. Diagram, photograph, sketch or drawing of the gunshot or shotgun wound
MODULE 11 – GUNSHOT WOUND
A. GUNSHOT WOUND (GSW) – It is an open wound produced by the penetration of bullet
slug within the tissues of the body. The bullet which was propelled from the gun as well as
the flame from the heated expanded gases in short range fire is the one that produces injury.
Three Basic Kinds of GSW Distinguished by the Proximity of the Weapon:
1. Contact – gun muzzle pressed against, or within an inch or two, of the body.
2. Close discharge – 6 inches to 2 ft.
3. Distance Discharge – over 2 ft. or 3 ft.
B. RANGE OF FIRE - an important aspect of forensic ballistics.
1. Muzzle Pattern – indicates contact wound and are often observed in suicide cases. The
whole charge (projectile, wads, if any, smoke, unburnt or semi-burnt powder particles
and hot gases) enter into the target. No burning, blackening and tattooing are observed.
Instead, they are observed inside the hole through careful examination. The edges are
found ragged (torn in star shape) and the wound is like an exit wound.
2. Scorching – caused by the flame or hot gases not by the hot projectiles as is commonly
believed, a.k.a. burning or charring.
3. Blackening – caused by the deposition of smoke particles by all types of powders at
close ranges. Being light particles, they soon lose their velocity and get deposited on any
material available in the path.
4. Tattooing (a.k.a. peppering) – caused by the embedding of unburnt and semi-burnt
powder particles into the surface of the target. These particles are slightly heavier than
the smoke particles. They retain motion to somewhat longer intervals and consequently
cause tattooing to a distance of about one and a-half times blackening range.
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C. OTHER GSW CHARACTERISTICS:
1. Pink Coloration – caused by absorbed carbon monoxide in the skin and flesh.
2. Dirt Ring – deposited by some projectile (which carry greases on them) around the
wound. Existence of this indicates the entrance side of a firearm injury & does not
indicate range.
3. Contusion – caused by the impact of the projectile (reddish dark to bluish black - varies
somewhat with the age of the injury). It takes the form of a belt around the wound. It is
of uniform in thickness.
4. Foreign Materials – Their presence not only permits the identification of the firearms
injury but they also permit a fairly reliable guess of firearm.
D. FACTORS INFLUENCING ENTRANCE AND EXIT GUNSHOT WOUNDS:
1. Kind of weapon - higher power the weapon, the more destructive to the tissues of the
body.
2. Caliber of the weapon - higher the caliber of the wounding bullet, the greater will be the
size of the wound of entrance, hence, greater destruction to the tissues.
3. Shape and composition of the missile - conical shape free end of the bullet slug has
more penetrating power but less tissue destruction, while bullet slug with hemispherical
free end had less penetrating but more destruction to the tissues.
4. Range of fire - the injury is not only due to the missile but also due to the pressure of the
heated expanded gases, flame and articles of gunpowder
5. Direction of fire - A right angle approach of the bullet to the body will produce a round
shape wound of entrance in short distance fire, while in acute angle of approach the
bullet will produce an oval shape wound of entrance with contusion collar widest on the
side of the acute angle of approach and a tendency for the bullet to deflect to another
direction upon hitting the target.
6. Part of the body involved - When the bullet hit the soft tissues of the body; the bullet
penetrates and usually without any change in direction, however upon hitting the bones
and other hard body structures the bullet may fracture the bones causing further injury or
may deflect to another direction.
E. DESCRIPTION OF THE WOUND OF ENTRANCE IS BASED ON THE DISTANCE
OF THE BODY FROM THE FIRED GUN:
1. Contact fire - burst due to the explosion of the powder which produces the heated and
expanded gases. There is burning of the tissues; singeing of the hair; and particles of
gunpowder in and around the wound of entrance; skin is separated from the underlying
tissues in the affected area and the blasted tissues are cherry red in color because of the
presence of carbon monoxide; pressure of the bullet will caused caving-in or excavation
of tissues and the contusion collar is seen around the wound of entrance.
2. Near contact up to six inches distance. There is bursting of tissues, burning and
blackening of the skin but the particles of gunpowder are present inside as well as around
the wound of entrance. The shape of the wound maybe lacerated or slit-like and the size
is larger than the diameter of the missile. The excavation of tissues due to the pressure
of the penetrating bullet slug but may as severe as in contact fire.
3. Distance above six inches up to 24 inches. The size of the wound gradually
approximates the size of the missile. The farther the target, the lesser the burning or
blackening of tissues, gun powder tattooing, singeing of the hair and excavation of
tissues and lesser until they disappear beyond the 24 inches distance.
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F. DIFFERENTIATION BETWEEN GUNSHOT WOUND OF ENTRANCE AND
WOUND OF EXIT
Differential points
Wound of Entrance
Wound of Exit
Size of the wound
• smaller than the missile
• bigger than the missile
Edge of the wound
• inverted
• everted
Shape of the wound
• round or oval
• no definite shape
Contusion collar
• present in contact
• absent
Gunpowder tattooing
• and near contact fire
• absent
Presence or absence
• always present
• maybe absent if logged inside
Protrusion of tissue
• Absent
• maybe present
Paraffin test
• positive in contact and near • negative
fire
G. DETERMINATION WHETHER THE GUNSHOT INJURY IS SUICIDAL,
HOMICIDAL OR ACCIDENTAL
1. Evidence to prove that gunshot wound is suicidal:
a. Accessibility of the involved part to the hand of the victim
b. Usually only one gunshot wound
c. Usually the distance is short range or class range
d. Presence of suicide note
e. History of frustration or despondency of the victim
f. Presence of cadaveric spasm on the hand of the victim
g. Exclusion of other evidences to prove that it is not suicide
2. Evidence that the gunshot wound is homicidal:
a. Wound is located at any part of the body
b. Victim usually at a certain distance from the assailant
c. Signs of struggle (Defense wound) maybe present in the victim
d. Disturbances of the surroundings.
e. Wounding weapon usually not found at the scene of the crime
f. Testimony from the witnesses
3. Evidence that gunshot wound is accidental:
a. Usually only one gunshot wound
b. Wound located at any part of the body
c. Absence of personal grudge between the victim and the one who fired the gun
d. Testimony from witnesses
H. POINTS TO CONSIDER IN THE REPORTING OF GUNSHOT AND SHOTGUN INJURIES:
1. Detailed description of the gunshot and shotgun wound
2. Location of wound in the body
3. Measurement of the wound as to diameter and depth
4. Number of wound of entrance and exit
5. Direction and length of the bullet tract
6. Organs or tissues involved
7. Location of the slug if lodged in the body
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8. Diagram, photograph, sketch or drawing of the gunshot or shotgun wound
I. EFFECTS OR COMPLICATIONS OF WOUND
1. Hemorrhage – Bleeding - loss of blood from the ruptured vessel secondary to trauma or
existing pathology.
2. Direct mechanical injury - direct damage to the tissues
3. Shock - disturbance of the balance of fluid in the body characterized by fall in blood
pressure, decreases blood flow or blood volume in the body.
4. Infection - appearance, growth and multiplication of the micro-organism in the living
tissues.
5. Embolism - clogging of the blood vessel by foreign bodies such as air or bits of fats or
septic embolus causing blocking to the blood flow to the distal tissues supplied by the
blood.
J. POINTS TO CONSIDER IN THE REPORTING OF WOUND:
1. Character of the wound
2. Location of wound in the body
3. Measurement of the wound
4. Number of wounds
5. Direction of wound
6. Organs involved
7. Severity of the wound
8. Period of healing or incapacity of the victim
K. OTHER PIECES OF EVIDENCE IN DEALING WITH THE WOUND:
1. Evidence from the wounding weapon
2. Evidence from the victim as well as the assailant
3. Evidence from the scene of the crime
L. STUDIES CONCERNING TERMINAL & WOUND BALLISTICS
1. 1857 – Monsieur Noiles, ‘Les Plaies Feu Courtes,’ his thesis dealt with the subject of
wounds made by small firearms.
2. 1889 – Mr. A. Lacassogne of Lyon, France, “La Deformation Des Balles de Revolver”
(Deformation of Revolver Bullets) in Volume 5. Archives de l’Antropologie Criminelle et
Des Sciences Penales.
3. 1748 - Henry Shrapnel, invented the shrapnel, which disperse its load of case shot whit a
small bursting charge, increasing the effective range of case.
4. Anomynous author, “Entrance Wounds and Powder Markings”.
5. Mr. Louis B. Wilson, “Dispersion of Bullet Energy in Relation to Wound Effects”.
6. P. Chavigny and E. Gelma, “Fissures of the Skull by Revolver Bullets at short-range”.
7. J. Howard Mathews. Chairman of the Department of Chemistry at the University of
Wisconsin. In this first criminal case, he was involved on the metallographic analysis of
bomb parts used to kill an individual.
8. Sir Sydney Smith – founder of the Medico-Legal Faculty at Cairo University and later
Regis Professor of Forensic Medicine at Edinburgh, was one of the leading exponents in
studying entrance and exit wounds, powder burns and powder “tattooing” on human skin
and other medical phenomena associated with gun fire.
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MODULE 13 - FORENSIC BALLISTICS
A. FORENSIC BALLISTICS - This is the real branch of the science which the police use as
their guide in field investigations. involves the examination of evidence from firearms that
may have been used in a crime. When a bullet is fired from a gun, the gun leaves microscopic
marks on the bullet and cartridge case. These marks are like ballistic fingerprints. If
investigators recover bullets from a crime scene, forensic examiners can test-fire a suspect’s
gun, then compare the marks on the crime scene bullet to marks on the test-fired bullet. The
examiner will then assess how similar the two sets of marks are and determine if the bullets
are likely to have been fired from the same gun or different guns. Cartridge cases are
compared in the same way.
Forensic Ballistics - The ballistics applied in the determination of legal evidence esp. as
concerned with the identification of firearms, ammunition, bullets, and cartridge cases
(Merriam-Webster)
Forensic - As applied to ballistics, or to any other subject, suggest a relationship to Courts
of Justice and legal proceedings.
Forum – It iss a Latin word from which forensic was derived, meaning a marketplace,
where people gather for "public disputation" or "public discussion". The terms "Ballistics",
Forensic Ballistics" and "Firearms Identification", have come to mean one and the same thing
in the minds of the public, and they can be used interchangeably.
B. STAGES OF FORENSIC BALLISTICS
1. Field Investigations - conducted by the first officers on the case in the field when they
investigate a case or cases wherein firearms have been used. This is a routine job of the
investigating officers, and this involves recognition, collection, marking, preservation, and
transmittal of ballistics exhibits like fired bullets, fired shells, firearms and allied matters.
2. Technical examinations of the ballistics exhibits - This is the job performed by the
firearms examiners in the laboratory. It involves marking of the evidence firearms, test
firings of evidence firearms to obtain test bullets and test shells for comparative purposes,
photomicrography under the bullet comparison microscope, preparation of comparative
charts, and the making of reports on the findings and observations of the firearms
examiners.
3. Legal proceedings - Court Trials - wherein the ballistics report of the firearm examiner
and the ballistics exhibits are presented during the trial of the case in a court of justice.
C. STUDIES IN RELATION TO FORENSIC BALLISTICS:
1. 1835 - Henry Goddard. In one of his case in England, where a homemaker was shot and
killed, he was able to identify the mold mark – the mold is used to manufacture lead balls
from molten leads – on the field projectile. He was the bullet, which could be traced back
to the mold. He also examined the paper patch – the paper patch provides the seal
between the ball gunpowder firearms – was able to identify it as having been torn from a
newspaper that was found on the room of the guilty servant.
2. Paul Jesrich, took photomicrographs of two bullets to compare, and subsequently
individualize them through the minute differences.
3. 1905 - Mr. Kockel, published an article entitled “The Expert Examination of Fired
Bullets”.
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4. 1912 - Professor V. Baltahazard. He devised a series of procedures to identify fired
bullets to the firearms from which they were fired. He studied the firearms by taking an
elaborate series of photographs of test fired bullet from the firearms as well as evidence
bullet. In 1913, he published the first article individualizing bullet markings.
5. 1922 - Mr. C. Williams, wrote “Fingerprints on Bullets” which appeared in Outdoor Life
magazine.
6. 1920 - R.E. Herrick, published “Ballistics Jurisprudence”.
7. November 1924 – Dr Sydney Smith. He wrote an article concerning the details of the
investigating that appeared in the British Medical Journal in January 1926. He relates that
he believes that scientific examination of firearms and projectiles in Great Britain had its
beginning as a result of the publication of his report on the case.
8. 1920 (Modern Era) - COL CALVIN H. GODDARD (M.D., U.S. ARMY) pioneered
the introduction of this science in Criminology courses in the different universities.
9. 1947 - Col Goddard came to the Philippines when Gen. Castaneda was ambushed
together with his aid, Col Salgado in Kamias, Quezon City, both died.
10. 1924 – Captain Edward C. ‘Ned’ Crossman. A well-known shooter and sports writer,
examined firearms evidence for the Los Angeles County Sheriff in April 1925, in New
York City, New York (USA), THE Bureau of Forensic Ballistics was established by C.E.
Waite, Major (later Colonel) Calvin H. Goddard, Philip O. Gravelle and John H. Fisher.
11. 1934 - Major Sir Gerald Burrard, wrote “The Identification of Firearms and Forensic
Ballistics”
12. 1935 Major Julian S. Hatcher, wrote and published; “Textbook of Firearms
Investigation, Identification and Evidence” together with the “Textbook of Pistols and
Revolvers.”
13. 1944 – John E. Davis. He joined the Police Department in Oakland, California
establishing its first criminology laboratory.
14. Derechter and Mage, wrote “Communication on the Identification of Fired Bullets and
Shells”.
15. Arthur Lucas, published “The Examination of Firearms and Projectiles in Forensic
Cases”.
16. Jack D. Gunther and professor Charles O. Gunther, published “The Identification of
Firearms”, which provided additional information about the principles of firearms
identification with approximately one-half of the book discussing in great detail the SaccoVanzetti case to include reprinting large portions of the actual court transcript
17. 1958 – John E. Davis, wrote “An Introduction to Tool Marks, Firearms and the
Striagraph” which provided excellent information about the examination and identification
of firearms and tool mark evidence.
18. 1996 – Tom A. Warlow, published “Firearms, the Law and Forensic Ballistics”
19. 1997 – Brian J. Heard, published “Handbook of Firearms and Ballistics Examining and
Interpreting Forensic Evidence”.
MODULE 15 - FIREARMS IDENTIFICATION
A. FIREARMS IDENTIFICATION. Sometimes incorrectly referred to as ballistics, firearms
identification can be defined as, the identification of fired bullets, cartridge cases or other
ammunition components as having been fired from a specific firearm (firearmsid.com).
In addition to comparing ammunition components to firearms, firearm examiners conduct
other examinations that usually include the following (firearmsid.com):
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1. Testing firearms to determine if they function properly.
2. Examine clothing and other items for gunshot residues and/or shot patterns in an attempt
to determine a muzzle-to-garment distance.
3. Determine caliber and manufacturer of ammunition components including the examination
of various shotshell components.
4. Determine the manufacturer or manufacturers of firearms that may have fired a particular
bullet or cartridge case.
B. GENERAL PRINCIPLES IN FIREARMS IDENTIFICATION (firearmsid.com)
1. Firearms identification is actually a form of Toolmark Identification where the firearm,
because it is made of a material harder than the ammunition components, acts as a tool to
leave impressed or striated marks on the various ammunition components that come into
contact with the firearm.
2. No two firearms, even those of the same make and model, will produce the same unique
marks on fired bullets and cartridge cases. Manufacturing processes, use, and abuse leave
surface characteristics within the firearm that cannot be exactly reproduced in other
firearms.
3. Firearms do not normally change much over time. This allows for firearms recovered
months or even years after a shooting to be identified as having fired a specific bullet or
cartridge case. Tests have been conducted that found that even after firing several hundred
rounds through a firearm the last bullet fired could still be identified to the first.
C. PRINCIPLES GOVERNING FIREARMS EXAMINATION
1. Bullet Identification
a. No two barrels and microscopically identical as the surface of their bores all possess
individual characteristics markings.
b. When a bullet is fired from a rifled barrel, it becomes engraved by the rifling and this
engraving on a bullet fired from one barrel will be different from that on a similar bullet
fire from another barrel. Conversely, the engraving on bullet from the same barrel will
be the same.
c. Every barrel leaves its “thumbmark” on every bullet which is fired through it, just as
every breech face leaves its “thumbmark” on the base of the fired cartridge case.
2. Shell Identification
a. The breechface and the striker of every single firearm leave microscopically
individualities of their own. The firearm leaves its “fingerprint” or “thumbmark” on
every cartridge which is fires.
b. The whole principle of identification is based on the fact that since the breechface of
every weapon must be individually distinct, the cartridge case which it fires is
imprinted with this individuality.
c. The imprints on all cartridges fired from the same weapon are the same and those
cartridges fired from different weapon must always be different.
MODULE 16 – FIREARMS IDENTIFYING CHARACTERISTICS
A. SCOPE OF ARMS MANUFACTURING PROCESS AND ITS RELATION TO
FIREARMS IDENTIFICATION – Before and after the manufacturing of firearms, the
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identifying characteristics of firearms are set. The following are the important stages in gun
manufacturing which determines the identifying characteristics of firearms.
1. Drilling - The process of manufacture starts with a solid steel bar which, when drilled
from end to end makes it is steel pipe. The interior surface at this stage bears numerous
scratches resulting from irregular cutting of the drill and the metal chips which mark the
finish.
2. Lapping - For smooth bore barrels, after the drilling process the inside of the barrel is
made very smooth.
3. Reaming - In barrels intended for rifles the next steps after drilling consists of “reaming”
and drilled hole for its entire length, this removes some of the sears and scratches. The
reamer removes metal from the entire surface because it is slightly larger in diameter than
the drill.
4. Rifling - If the barrel is to be rifled it is done with the use of modern tools which
automatically cut the spiral grooves on the inside the barrel and impart to every firearms’
characteristics which are peculiar to the barrel.
5. Another phase of firearm manufacture which is of great importance to the identification of
firearms is finishing operations of the breechface of the breechblock of the firearm. It
is that portion of the firearm against which the cartridge is fired.
B. TWO (2) GENERAL CHARACTERISTICS REGARDING FIREARMS
IDENTIFICATION
1. Class Characteristics – These are characteristics which are determinable even before the
manufacture of the firearm. It is categorized into the following a. Caliber
b. Number of Lands and Grooves
c. Width of Lands and Grooves
d. Twist of riflings
e. Pitch of the rifling
f. Depth of grooves
Class characteristics of different firearms a. Colt Type ---------------------------------------- .45 6L G2X
b. Grease Gun ------------------------------------- .45 6R G+
c. Smith and Wesson Rev. ---------------------- .45 6R GL
d. Smith and Wesson Rev. ---------------------- .38 5R G=L
e. Colt Revolver ---------------------------------- .38 6L G+
f. Colt Pistol Super-------------------------------- .38 6L G+
g. Colt Revolver ----------------------------------- .32 6L G+
h. Colt Pistol --------------------------------------- .32 6L G+
i. Colt Pistol --------------------------------------- .25 6L G2X
j. Colt Revolver ----------------------------------- .22 6L G2X
k. Colt Revolver ----------------------------------- .357 6L G2X
l. Smith and Wesson Rev. ---------------------- .32 5R G=L
m. Smith and Wesson MRF Rev. ---------------- .22 6R G=L
n. Enfield Revolver -------------------------------- .38 7R G2X
o. US Carbine -------------------------------------- .30 4R G3x
p. Browning Pistol --------------------------------- 9mm 6R G=L
q. Star Pistol ---------------------------------------- .380 6R G+
r. Llama Pistol ------------------------------------- .380 6L G+
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s. Beretta Pistol ------------------------------------.32 6R G2X
t. Astra Pistol -------------------------------------- .32 6R G2X
u. Arminius Revolver ------------------------------ .22 6R G2X
v. Burgo Revolver --------------------------------- .22 8R G+
w. Marlin M57 Rifle -------------------------------- .22 2OR G+
2.
Individual Characteristics – These are characteristics which are determinable only after
the manufacture of the firearm. Their existence in a firearm is brought about by the tools
in their normal operation resulting through wear, tear, abuse, mutilations, corrosion,
erosions and other fortuitous causes. These are the irregularities found on the inner
surface of the barrel and on the breech face of the breechblock of the firearms as a result of
the failure of the tool beyond the control of the manufacturer to make them smooth as a
minor. The Association of Firearm and Tool Mark Examiners (AFTE) Glossary defines
Individual characteristics as:
“Marks produced by the random imperfections or irregularities of tool surfaces.
These random imperfections or irregularities are produced incidental to
manufacture and/or caused by use, corrosion, or damage. They are unique to that
tool and distinguish it from all other tools” (as cited by firearmsid.com).
MODULE 17 - MARKS ON FIRED BULLETS AND FIRE CARTRIDGE CASES
A. MARKINGS APPEARING ON A FIRED CARTRIDGE CASE
1. Breechface marks
2. Firing pin impression
3. Ejector mark
4. Extractor mark
5. Chamber mark
B. TWO TYPES OF MARKINGS (individual)
1. Impression type – those markings caused by direct pressure contact. (ex. Breechface
mark)
2. Striated mark – those markings caused by sliding contact. (ex. Minute striations on the
cylindrical surface of the bullet)
C. RELATED TERMINOLOGIES:
1. Abrasion (in the bore) – Scratches caused by using improper cleaning materials, or by
firing ammunition with bullets to which abrasive material was adhering.
2. Accidental Characteristics - characteristics or marks left by some individual gun that
occurred on that particular shot and may or may not reproduced on any other shots.
3. Ballistician – Person whose knowledge in firearms identification is accepted by the courts
and other investigation agencies.
4. Definitive Proof – after the gun is finally completed, it is again fired with a heavy charge
to ensure against accident. This is the definitive proof and guns passing this test are
stamped with still another marked. Belgium is the great center for the manufacture of
5. Expert - all witnesses whose opinions are admitted on grounds of specialized knowledge,
training and experience.
6. Fouling - accumulation of a deposit within the bore of a firearm caused by solid byproducts remaining after a cartridge of is fired.
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7. Heavy Rusting - Usually called corrosion rather than fouling.
8. Proof Marks – examination and testing of firearms by a recognized authority according to
certain rules and stamped with a mark to indicate that they are safe for sale and used by the
public.
9. Provisional Proof – the testing of the rough gun barrels and fired with a heavy charge of
powder to see if they are strong enough to be finished and assembled into gun.
10. Secondary Firing Pin Impression – Is a mark on the side of the regular impression
usually found in pistols.
11. Shaving Marks – a shaving on the ogive portion of the fired bullet due to poor
alignment of the cylinder with the barrel. This shaving is often found in the revolver.
12. Skid Marks – When the bullet first starts forward without turning, that before the bullet
can begin to turn, it moves forward a small distance and this makes the front of the groove
in the bullet wider than the rear part. This skidding is more pronounced in revolvers.
13. Slippage Marks – Scratches of the fired bullet due to badly worn rifling or when the
bullet is small or too soft for the velocity used, there is a tendency for it to go straight
forward without turning and it jumps the rifling or slips.
14. Stripping Marks – scratches on the fired bullet due to worn out barrel.
D. TECHNIQUES OF EXAMINATION
1. Physical – Evidence bullets, cartridge cases and suspected firearm once submitted by the
requesting party will be physically examined to determine its markings or initials made by
the investigator for identification purposes. If no identifying marks were found the
firearms examiner will, before anything, affix his own identifying markings or initials
derived form the names of the requesting party, victim or suspect in that order of priority.
The firearm will also be physically examine to determine its safety devices seeing to it that
there is no cartridge inserted in the chamber that will cause accidental firing. Likewise, it
will be examined of its vital parts whether or not it is in operating condition and a tag will
be attached for distinction.
Bullets of different class characteristics will be segregated from one another especially
the determination of caliber, number of lands and grooves, twist of rifling, etc. to facilitate
its easy final microscopic examination.
Cartridge cases will also be segregated to determine the caliber, type and make of
firearm from which they were fired. Misfired or dud cartridges will also be taken into
consideration. Although they may not have any ballistics probative value, yet, they may
give a clue to the solution of a crime.
2. Test Firing – The firearm is test fired before a bullet recovery box in order to obtain test
bullets and test cartridge cases for comparison with the evidence bullets and cartridge
cases, respectively. But before firing, the cartridge will be marked at the side of the case
and on the nose portion of the bullet with letter “T” (to represent test) followed by the last
two digits of the serial number of the firearm of the test to be made (eg) T-77-1 to T-77-3
in their order of firing to distinguish the number 1 test from the number 2 or 3 as the case
may be.
3. Microscope Examination – After the recovery of the test bullets and cartridge case, they
will be compared with the evidence cartridge cases under the Bullet Comparison
Microscope to determine whether or not they have the congruency of striations or the same
individual characteristics.
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E. IDENTIFICATION OF FIRED BULLETS AND CARTRIDGE CASES
1. The first thing to do in the examination of bullets is to conduct a visual examination of the
bullets in order to familiarize with all markings appearing on it.
2. Conduct examination of the bore of the firearm.
3. Determine the conspicuous characteristics appearing on the bullet or any markings
appearing therein.
4. Markings appearing on the test bullet No. 1 and does not appear on the succeeding test
bullet such markings should be disregarded. Consequently, such markings are called
accidental markings which came from foreign substances.
5. cylindrical passage of the expending gas will appear dark or black in the picture.
F. WHAT TO COMPARE?
1. Evidence Bullet
2. Test/Standard Bullet - Before proceeding in the examination of the firearm by means of
the fired bullets, first identify the particular firearm through the class characteristics
appearing on the cylindrical surface of the bullet.
G. IMPORTANCE OF FIRED BULLET IN FIREARMS IDENTIFICATION
1. By means of fire bullet you can determine the particular barrel of firearm used.
2. Recovered bullet can tell the type, caliber and make of firearm from which it was fired.
3. Can determine also the condition of the firearm us
H. FIREARM CARTRIDGE CASE
Before proceeding in the examination, conduct a preliminary examination on the cartridge
case having a visual examination on the condition of such cartridge case. Determine whether or
not it came from a revolver or from an automatic pistol and sub-machine guns. Examine those
markings that are present on the base portion, the breechface marks, firing pin impression, the
location of the extractor and ejector markings. Check also the markings caused by the chamber
of the firearm. The magazine and the ejector port markings must also be taken into consideration
particularly those cartridge cases from gums having full automatic mechanism.
I. BULLET COMPARISON MICROSCOPE
This instrument consists of two single tubes fitted with a cross arm and comparison
eyepiece, in which the images of two objects held on its two adjustable stages are fused into one,
forming a single image as can be seen on the comparison eyepiece. The microscope tubes are
built as a unit with the comparison eyepiece which has a prism arrangement that brings the
images of the specimen held under the microscopic tubes into a side by side position in the left
and right side of the eyepiece field the eyepiece is threaded for focusing on the dividing line
between the two fields.
Under the microscope the two fired bullets or fired cartridge cases can be examined in a
“juxtaposition” and whatever the observation and findings obtained during the examination can
be photographed for court presentation and also to give the Court a better understanding and
good appreciation of how he came to that conclusion.
J. FINDINGS/CONCLUSION
Findings are the bases of conclusion. A conclusion cannot be made without the findings. A
good conclusion is always based on good findings. In comparative examination of the evidence
bullet that are found on the periphery running from the forward shoulder to the base portion
(these are surface of the barrel), are discernible with the test bullet or if they have the
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congruency, correspondence or intermarriage, then the evidence bullet and the test bullet were
fired from one and the same firearm. For conclusive of findings, there should be at least three (3)
tests that should be compared. The first is for preliminary, the second is for confirmation and
the third is for conclusion. This is also true for fired cartridge cases. Although the individual
characteristics of the cases may be found at the base portion where breechface, ejector, extractor
markings are found on the sides that are in contact with the inner surface of the chamber.
Clip or magazine markings may also give discernible markings. Like the ejector or
extractor markings if considered singly may not be a basis for conclusion. These only serve as
corroborative characteristics but certainly lack legal significance. This is so because the case
may have these markings even if they were unloaded from the firearm without firing. As a rule,
the point of the examination and comparison is at the area of the primer proper where breechface
markings together with the firing pin impression are located. Primers are softer metals and
receive more prominent striation than any other portion of the base.
Conclusion is the opinion gathered from the finding. This is the end result of the
examination and should be taken seriously as it involves the life and liberty of the suspect. When
the evidence and the test bullets or cartridge cases have the same individual characteristics, the
competent examiner will conclude that they were fired from one and the same individual
characteristic; the competent examiner will conclude that they were fired from one and the same
suspected firearm. If they have different individual characteristics, certainly, the evidence bullet
or case was not fired from the suspected firearm. Where the evidence has prominent or minor
striations that the three tests, it calls for uncertainty and doubt for a positive or negative
conclusion. Only those evidence bullets or cases that have the same individual characteristics
may be taken of photomicrograph for Court presentation.
K. REQUIREMENTS FOR A POSITIVE IDENTIFICATION
1. Prominent – Standing out or projecting beyond a surface or line, readily noticeable.
2. Consistent – Possessing firmness. The impression or striation found on the evidence
bullet or cartridge case appearing in every test bullets and cartridge cases.
3. Significant – The markings have meaning or capable of being interpreted by the
Firearms Examiner or Ballistician.
L. INSTRUMENTS USED IN FORENSIC BALISTICS
1. Analytical or Torsion Balance – for determining weights of bullets and shotgun pellets
for possible determination of type, and make of firearm from which it was fired.
2. Bullet Comparison Microscope – designed to permit the firearms examiner to
determine the similarity and dissimilarity between two fired bullets or two fired shells,
by simultaneously observing their magnified image in a single microscopic field.
3. Bullet Recovery Box – Traditionally, it consist of a wooden (or metal) box, 12 “x”12”x
96
(del
Rosario,
1996)
or
18”x18”x10’
(http://projects.nfstc.org/firearms/module07/fir_m07_t13_03.htm), with a hinged to
cover and with one end open. It is usually filled ordinary cotton and separated into
sections by cardboard partitions.
4. CP–6 Comparison Projector – very much similar with the bullet comparison
microscope, where 2 fired bullets or shells can be compared in one setting of the firearms
examiner.
5. Filan Micrometer Eye Piece - a measuring microscope to read the width of the land and
groove marks and to obtain the pitch of the rifling in turns per inch.
6. Helixometer – used in measuring pitch of rifling firearms. This instrument is generally
used in high advanced ballistic laboratory.
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7. Machine Rest - use for testing the accuracy of a firearm.
8. Caliper – used for making measurements such as bullet diameter and bore diameter.
9. Micrometer – similar in use as caliber.
10. Onoscope – a small instrument sometimes used in examining the internal surface of the
gun barrel in determining the irregularities inside the bore of the gun barrel. It has a tiny
lamp at the terminal portion and this is inserted inside the bore for internal examination.
11. Optical Sight – sight containing series of lenses to form an optical system being
contained in one unit. Optical sights do not necessarily have telescopic properties. The
optical system may merely include range indicating, or range estimating devices, plus the
necessary means of adjusting for elevation and wind age.
12. Shadow Graph – contains a series of microscopic lenses of different magnification that
can be used in examining fired bullet or fired shells to determine their class
characteristics and also for orientation purposes. It greatly differs from the bullet
comparison microscope and stereoscope microscope that this instrument contains a large
ground glass, 14 inches more or less in diameter, wherein the observation and
comparison of the class characteristics is done by the firearm examiner.
13. Stereoscopic Microscope – used in the preliminary examination of fired bullets and
fired shells to determine the relative distribution of the class characteristics or for socalled orientation purposes. It can be used also in the close-up examination of tempered
serial numbers of firearms.
14. Taper Gauge – for determining bore diameter of firearms. This instrument is very useful
for giving quick idea as to the caliber of a gun.
15. Telescope Sight – an optical employing the principle of the telescope to enlarge the
image of the target.
REFERENCES:
Unpublished notes and handouts, University of Baguio and University of the Cordilleras
Forensic Ballistics by del Rosario
Wikipedia and other open internet sources as earlier cited
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