Firearm Bullet and Cartridge Case Comparisons
Click on images to enlarge

          Bullet comparisons and cartridge case comparisons are routinely used to compare evidence bullets and cartridge cases using a comparison microscope (as shown) against test fired bullets and cartridge cases from a known firearm.

           This photomicrograph shows a microscopic comparison and identification between an evidence fired cartridge case recovered from the scene of a shooting related homicide (shown on the above right) and a fired cartridge case (shown on the above left) found 11 years later at a location which was disclosed to the police by a witness who had seen the suspect test fire the pistol used in the crime.

           These two images are examples of microscopic bullet comparisons showing the evidence bullet on the left half of each screen and the test fired bullet on the right half of each screen.

          The images shown above show a difficult microscopic comparison involving a .22 caliber firearm. The evidence fired cartridge case (first photo) had insufficient microscopic detail for a match using the firing pin indentation. The match was made, however, by using the chambering marks (other two photos) on the side of the cartridge case. Chambering marks such as those only occur as a product of the firing of the firearm.

          This image shows a typical cartridge case comparison using breechface markings along with the firing pin impressions.

          This microphotograph depicts a typical Glock pistol cartridge case (shown on the left side of microphotograph) which was recovered at the scene of an officer involved shooting incident and one of the test fired cartridge cases (shown on the right side of microphotograph) from the officer's Glock 9mm model 26 pistol.

          This shows a comparison of two evidence cartridge cases which were fired in different pistols (an elimination).