Forensic Ballistics (2)
What is the primary role of the firing pin in a firearm?
To ignite the priming mixture of a cartridge
What happens when the firing pin strikes the primer of a cartridge?
The primer explodes or the primer's compound ignites.
What must be true about the priming mixture for it to ignite effectively?
It must be live, potent, and free of any mixture
What is the result of the ignition of the priming mixture?
It produces a small flame that ignites the gunpowder
What happens gunpowder combusts?
The combustion of the gunpowder creates gases that propel the bullet out of the barrel.
What does the high-pressure gas created by the combustion of gunpowder do?
It forces the bullet down the barrel
What is the law of interaction that explains recoil?
For every action, there is an equal and opposite reaction
What effect does the amount of powder in a cartridge have on the bullet?
It affects the bullet's speed and stability
In a smooth-bore weapon like a shotgun, how does the bullet travel?
It moves forward without rotation
What is the main effect of the energy generated by the ignition of gunpowder on the bullet?
The energy generated is transferred to the bullet, which accelerates the bullet to high speeds as it travels through the barrel.
What defines the "Accurate" range of a firearm?
The distance within which the shooter has control over their shots and accuracy to hit the target
What is typically considered the "Zero range" in terms of accuracy?
Zero range is the farthest distance wherein the shooter still has control and accuracy to hit the target. (Usually 5 meters)
What is the "Effective" range of a firearm?
The distance at which a bullet is still capable of inflicting fatal injury
What factor determines the "Maximum" range of a firearm?
type of gun
How does the firing speed of a firearm affect its effective range?
The faster you fire the firearm, the better.
What is typically the farthest distance at which a shooter can control their shots and maintain accuracy?
Zero Range
What is the approximate speed of a bullet in feet per second?
2,700 ft/sec
What is the approximate speed of a bullet in kilometers per hour?
3,000 km/hr
What term describes the resistance a bullet encounters during its flight?
Air Resistance
Which type of air resistance is caused by pressure at the head of the projectile?
Bow
What is "Skin Friction" in the context of bullet flight?
Friction of air along the middle portion of the bullet's body
What type of air resistance is associated with the pressure and air behind the base of the bullet?
Base Drag
It is the downward reaction of the bullet towards the center of the Earth
Pull of Gravity
What does "Penetration" refer to in terms of bullet impact?
The depth of entry of the bullet into the target based on its power and velocity
According to Article 254 of the RPC, what must be proven for a charge of discharging a firearm?
1. That the offender discharges a firearm against or at another person; and,
2. That the offender has no intention to kill that person.
What factors influence the penetration depth of a bullet?
- power
- velocity
It is the combined effects of all forms of resistance encountered by the bullet during flight
Aerodynamic Drag
This deals with the effect of the impact or projectile on the target.
Terminal Ballistics
It is the energy of the bullet when it hits the target.
Terminal energy
What characteristic of a bullet does "Shocking Power" describe?
Power of the bullet results to the instant death of the victim
What does "Terminal Velocity" measure?
The speed of the bullet when it hits the target
What does "Terminal Penetration" refer to?
The depth of the bullet’s entry into the target
Which characteristic of terminal ballistics is measured by the size of the bullet groupings on the target?
Terminal Accuracy
Which phase of forensic ballistics is conducted by the first responder at the crime scene?
Field Investigation
What is the primary focus of the "Technical Examination of Ballistics Exhibits" phase?
To determine the value of firearms ammunition in crime solving.
In which phase of forensic ballistics are the results of examinations presented before the court?
Legal Proceedings
Who was the one who killed John F. Kennedy on 22 November 1963?
Lee Harvey Oswald
What type of damage involves the creation of a permanent wound channel?
Crushing
In forensic ballistics, what does "Cavitation" refer to?
The ability of body tissue to return to its original shape
Which damage type creates a concentrated spiral of pressure that pushes tissue away from the piercing?
Cavitation
What is "Yaw Motion" in the context of bullet damage?
Unstable Rotation or Tumbling
What is the acoustic wave that travels through tissue before the projectile?
Shock Wave
Who was involved in the assassination of Martin Luther King Jr.?
James Earl Ray
Which type of cavity is described as being 30 times the diameter of the projectile?
Temporary Cavity
Which case is associated with Mario Teodoro Failon Etong?
Trinidad Etong Case
What is the purpose of the "Field Investigation" phase in forensic ballistics?
To conduct the initial investigation at the crime scene
Which damage type involves the destruction of tissue caused by a projectile?
Laceration
This is a type of cavity wherein a hole is left by the passage of projectile.
Permanent Cavity
It is the study of the effect of the projectiles on the target and the conditions that affect them.
Wound Ballistics
What type of gunshot wound involves the projectile passing all the way through the body?
Perforating/Transfixing
What is a distinguishing feature of a "Penetrating" gunshot wound?
Wound only has entrance. Object enters to the body and does not pass through.
Which type of gunshot wound is characterized by having only an entrance wound and does not pass through the body?
Penetrating
What type of gunshot wound occurs when the firearm is within 2 inches of the body?
Direct In Contact
What type of gunshot wound is likely to have smudging or burn marks from the bullet?
Direct in Contact
Which type of gunshot wound is associated with tattooing or small punctuate abrasions on the skin?
Close Discharge
What kind of gunshot wound is characterized by having no specific area of the body involved and is usually a single shot?
Accidental
Which of the following is not a piece of evidence typically associated with suicidal gunshot wounds?
The shot is usually accompanied by multiple wounds.
Which characteristic of gunshot wounds indicates the presence of carbon monoxide in the skin and flesh?
Pink Coloration
What is a "Contusion" in the context of gunshot wounds?
It is caused by the impact of projectile (reddish dark to bluish dark)
Which type of damage in gunshot wounds involves a permanent cavity and a temporary cavity?
Cavitation
Which of the following is a characteristic of a gunshot wound from a distance of over 2 feet?
No special marks, no specific area of body involved
It is a characteristic of gunshot wounds that is shown in the entrance wound.
Dirt Ring
Who introduced the Bullet Comparison Microscope?
Col. Calvin H. Goddard
What does the Bullet Comparison Microscope allow forensic examiners to do?
Compare the similarity and dissimilarity between two fired bullets or cartridge cases
What technique involves merging the same magnification and plane of two images in the Bullet Comparison Microscope?
Intermarriage
Which tool is generally used for preliminary examination of fired bullets and shells, and can also be used to examine tampered serial numbers on firearms?
Stereoscope Microscope
What is the primary advantage of using a Comparison Projector (CP6) over a Comparison Microscope?
It allows for a side-by-side comparison of images on a large screen
What is the function of a Bullet Recovery Box in forensic ballistics?
It is for obtaining best fired bullet or test fired cartridge cases from the suspected firearms submitted to the ballistics laboratory.
Which tool is used to determine the weight of bullets, shots, and pellets for identifying the type, caliber, and make of a firearm?
Analytical Balance
What does the Helixometer measure in forensic ballistics?
Pitch of rifling
What type of gauge is used to determine the diameter of the bore of a firearm?
Taper gauge
Which device is used to determine the speed of a bullet or muzzle velocity?
Chronograph
Which instrument is used for examining the interior surface of a barrel?
Onoscope
Which type of microscope allows simultaneous viewing of two magnified images of fired bullets or cartridge cases?
Comparison Microscope