Ballistics Overview

Study Notes

The science of studying projectile motion and the factors affecting it
Projectiles are objects fired from firearms, including metallic and non-metallic types
Motion refers to projectile movement from leaving the shell and gun muzzle until reaching the target or falling to the ground

Internal Ballistics: Deals with what happens inside the firearm during firing
- Combustion of propellants
- Gas pressure build up
- Projectile acceleration
- Barrel pressure
- Projectile exit velocity at the muzzle
- Temperature and humidity inside the barrel
External Ballistics: Studies the projectile's movement after leaving the muzzle
- Muzzle blast, the noise produced at the muzzle point
- Muzzle energy, the force generated measured in foot-pound force
- Trajectory, the projectile's parabolic flight path
- Range, the distance between the muzzle and the target
- Velocity, the projectile's speed during flight usually measured in feet per second (ft/sec)
- Gravity, the downward force pulling the bullet towards the earth
- Air resistance, the force the air exerts on the bullet during flight
Terminal Ballistics: Focuses on the impact of the projectile on the target
- Projectile's penetration
- Energy transfer
- Damage caused to the target
- Ricochet, the projectile's deflection from the target
- The projectile's yaw (change in angle during flight)

Field Investigation: Examining the crime scene for ballistic evidence
- Collecting fired cartridges and projectiles
- Documenting the location and position of evidence
- Photographing the scene and evidence
Technical Examination: Analyzing ballistic evidence in a laboratory
- Comparison of fired bullets and cartridges to determine if they match
- Determining the type of firearm used
- Reconstructing the trajectory of the bullet
Legal Proceeding: Presenting ballistic evidence in court
- Testifying as an expert witness
- Explaining the findings of the technical examination
- Providing opinions on the case based on the evidence

Definition: A weapon designed to propel a projectile using the rapid expansion of gases produced by the combustion of a propellant
Components: Barrel, action, stock, sights, and firing mechanism
Classifications: Handguns, rifles, shotguns, submachine guns, machine guns
Firearms History: Invention and evolution of different types of firearms

Calvin H Goddard: Father of modern ballistics who used techniques to match bullets to a specific firearm
Daniel B. Wesson: Partnered with Smith in revolver manufacturing
David "Carbine" Williams: Made the first known carbine
Alexander John Forsyth: Developed percussion ignition, replacing flintlock technology
John Mahlon Marlin: Founder of Marlin Firearms Company
James Wolfe Ripley: Promoted the development of the Model 1855 rifle-musket
Henry Deringer: Developed a class of firearms named after him, including pistols and rifles
John C. Garand: Designed and invented the semi-automatic US Rifle, Caliber .30, M1
Oliver F. Winchester: Early manufacturer of rifles and pistols
Major Uziel Gal: Designed the UZI submachine gun in 1950
George Hyde: Known for his work with submachine guns, contributing to the design of the M3A1 (Grease Gun)
Eugene Stoner: Designed the M16 rifle, initially for Armalite, later licensed to Colt Company
Professor Victor Balthazard (1913): Published the first article on individualization of bullet markings
R.E. Herrick (1920): Published an article titled "Ballistics Jurisprudence"

Hammer forging: A process that produces a seamless barrel
Rifling: Grooves cut spirally inside the barrel to create spin which improves accuracy and range
Barrel finish: Polishing or coating to protect the barrel from corrosion

The breach area: The rear end of the barrel where the cartridge is loaded
Breechface: The flat surface against which the cartridge case head seats
Marks left on the breechface: Ejector marks, firing pin marks, and extractor marks