Ballistics Flashcards
Define:
a. Ballistics
b. Firearm
c. Bullet
d. Caliber
a. The study of projectile motion and effects
b. A rifle, pistol, or other portable gun
c. The projectile expelled from a firearm
d. The diameter of the firearm barrel bore
How can GSR assist a CSI in identifying intent?
Determines close range or long range as well as if it was recent
How to calculate angle of impact?
Analyze bullet trajectory and impact marks/damage pattern.
sin-1(Major axis/Lower axis)
How to determine shooter height/distance?
Estimate based on bullet trajectory and impact angle analysis.
Height of shooter-victim eye level/tan(angle of elevation)
Rifle vs Shotgun
Rifle has longer barrel, fires single projectile.
Shotgun has shorter barrel, fires multiple pellet projectiles.
Purpose of rifling?
Spiral grooves that spin/stabilize the bullet trajectory.
Distinguish revolver and semi-auto.
Revolver has revolving cylinder. Semi-auto uses single fixed magazine.
Distinguish semi-auto and fully auto.
Semi reloads after each shot. Fully auto fires continuously when trigger depressed.
Name 4 .38 caliber family members.
.38 Special, .357 Magnum, .38 S&W, .38 ACP
3 firearm databases and agencies?
Drugfire, IBIS, NIBIN (National Integrated Ballistics Info Network
4 markings for ballistics ID?
Lands and grooves
Firing pin strike marks
Breech face markings (primer residue/marks from breech)
Iternal Ballistics.
Transitional Ballistics.
External Ballistics.
Terminal Ballistics.
GSR components and test?
GSR contains nitrates/nitrites from nitrocellulose and trace unburnt powder
Paraffin test for nitrates
Primer residue and analysis method?
Lead, barium, antimony. Scanning electron microscopy.
How to restore obliterated serial #?
Polishing
Chemical restoration with acids/bases, magnetic, electromagnetic
Firing sequence mechanics?
Trigger pull, hammer strikes Firing pin, strikes primer, Powder ignites, Bullet expelled, Case ejects/Slide recoil
