AFTE Store - The Examination and Comparison of Bolt Rotation Marks on Cartridges Cycled and Fired In Various 223 Caliber AR-15 Type Rifles

If bolt rotation marks are the result of firing in, and not the result of cycling through the action, of a .223 caliber AR-15 type rifle, then the bolt rotation marks on fired cartridge cases would provide beneficial information to the firearm examiner regarding their examination of identifiable individual characteristics in the absence of a firearm. Seven AR-15 type rifles and three different brands of ammunition were used in this research. Cartridges were either fired or cycled through the action of each firearm. Bolt rotation marks were produced on both the cycled cartridges and the fired cartridge cases. These rotation marks could therefore only be used to determine that the tests were worked through the action of the firearms.

Full Journal: AFTE Journal Vol 52 No 1 (2020)