More Related Content
More from eew18
Recently uploaded
Recently uploaded (20)
Firearms 1
- 14. Jacketed soft point Lead round nose Wad - cutter Full – metal jacket Jacketed hollow point Semi wad-cutter
- 22. Individual Class Striae Bullettype Firing pin marks Bullet caliber Bullet weight Breech marks Lands and grooves Extractor marks Rifling Ejector marks Cartridge case Chamber marks Head stamp
Editor's Notes
- http://science.howstuffworks.com/revolver2.htmhttp://science.howstuffworks.com/machine-gun4.htm
- the combustion products are expelled therefore a presence of lead, barium and antimony confirm discharge of a firearm
- Round nose & full metal jacket – pass through a target when they don’t hit something significant like bone
- Big focus today in bullet design – bullet that has an expanding point – expansion is needed to slow down the bullet when it strikes an object A bullet that expends all of its energy in a target is more efficient and produces more damageneed a bullet to pass through a car window , heavy clothing
- .32 caliber S&W – 5 lands and grooves with a right hand twist (clockwise).32 caliber Colt – 6 lands and grooves with a left hand twist (counterclockwise)
- parallel set of scratches on a bullet caused by markings on the bore can be matched to a weapon or bullets from other crime scenesmicroscope is necessary to see marks
- Head stamp -numerals, letters, symbols on base of cartridge showing manufacture caliber and code Rim – primer on circumference base Centerfire – primer in center of base
- Dawson Meets Basil in "The Great Mouse Detective" - you tube