1. Ballistic Analysis Note #2

2. Bullets to Guns • It is extremely difficult to convict someone of a murder without possession of the murder weapon • Matching a bullet with a gun is essential in most cases of shooting • Striations on bullets • Impressions on cartridge cases

3. Striation • Bullets become scarred by rifling as they travel down the barrel of a gun • No two rifle barrels have identical striated markings

4. Striations

6. Matching Procedure Fire bullets from a suspected weapon With the aid of a comparison microscope, compare these “test fires” to the suspected bullets Striations must be identical for a positive match

7. Comparison Microscope Two scopes in one field

10. Cartridge Cases • The weapon’s firing and loading mechanisms impress the shell with markings • The impression of firing pin into the primer • Other surface markings on cartridge case • The markings on the shell can be compared to determine the suspected weapon

11. Impression on Primers

13. Markings on the Cartridge Cases https://www.youtube.com/watch?v=sBKJZTkbypo&feature=player_embedded

14. Other Information from Ballistic Analysis Gunpowder: assessment of the distance of weapon and wound up to 4 feet Effects on target: type of firearms Primer residue on the hand: identification of the shooter Serial number of the firearm: identification of the weapon