1. Ballistics: Introduction
Ballistic evidence helps explain:
Ref: Forensic Science: Fundamentals & Investigations, Chapter 17 Bertino

2. Long Guns and Handguns Long guns Handguns Automatic and Semi-automatic
Forensic Science: Fundamentals & Investigations, Chapter 17

3. Firearms and Rifling
Forensic Science: Fundamentals & Investigations, Chapter 17

4. Bullets, Cartridges, and Calibers
Semi has 10 cartridges in a magazine (clip)
The bullet, usually of metal, is out front with the cartridge, holding the primer and propellant powders, behind.
Forensic Science: Fundamentals & Investigations, Chapter 17

5. How a Firearm Works
Forensic Science: Fundamentals & Investigations, Chapter 17

6. How a Firearm Works
Forensic Science: Fundamentals & Investigations, Chapter 17

7. Caliber of the Cartridge
Caliber—a measure of the diameter of the cartridge (stamped on headstamp on the bottom of the cartridge casing)
In hundredths of an inch
Common calibers include .22, .25, .357, .38, .44, and .45
Why should the caliber of ammunition match the firearm that shoots it? If they do not match, what could go wrong?
Forensic Science: Fundamentals & Investigations, Chapter 17

8. The Study of Bullets and Cartridge Casings
Forensic Science: Fundamentals & Investigations, Chapter 17
How is each fired bullet marked?
What is the procedure to match a spent bullet to the firearm that shot it?
What makes up a test-firing, and why is it done?

9. Marks on the Spent Cartridge Casings
Firing pin marks
Breechblock marks
Extractor marks
Ejector marks
Forensic Science: Fundamentals & Investigations, Chapter 17

10. Gunshot Residues Gunshot Residues (GSR)
Forensic Science: Fundamentals & Investigations, Chapter 17

11. Trajectory Two reference points are needed to define the trajectory
Investigators can figure the shooter discharged the firearm somewhere along that line
Forensic Science: Fundamentals & Investigations, Chapter 17

12. Trajectory Reference points can be
bullet holes in objects or victims
An entry point and exit point on a victim
Gunshot residue or spent cartridge casings
Lasers can trace a straight-line path to determine the position of the shooter
Forensic Science: Fundamentals & Investigations, Chapter 17

13. Determining the Location of the Shooter
Building is 60 feet away along the horizon line Bullet hole is 4 feet above the ground
Where is the shooter located?
Forensic Science: Fundamentals & Investigations, Chapter 17

14. Triangulation B is where the shooter is located; find the length of BC
The Abc triangle has the same proportions as the ABC triangle
Forensic Science: Fundamentals & Investigations, Chapter 17

15. Triangulation Using Pythagorean’s theorem AB2 = AC2 + BC2
Forensic Science: Fundamentals & Investigations, Chapter 17

16. Bullet Wounds
Why do entrance wounds tend to be smaller than exit wounds?
If the bullet penetrates clothing, what can fibers embedded in the wound indicate?
Where is gunshot residue usually found?
If the gun is fired with the muzzle touching the victim’s skin, what telltale mark may show up?
Will larger or will smaller caliber bullets tend to lodge within the body rather than passing through? Why?
Forensic Science: Fundamentals & Investigations, Chapter 17
Kennedy assassination recreation