EXPANDING HANDGUN BULLETS

Background: Many new types of expanding or fragmenting handgun ammunit ion have been developed, Knowledge of these unusual bullets may aid in the management of patients and their wounds. Methods: Eleven differen t expanding or fragmenting .45 caliber bullets and a nondeforming, ful l metal jacketed bullet for comparison were fired multiple times from the same handgun into both a water reservoir and ordnance gelatin, Per formance was observed and recorded. Muzzle velocities were measured us ing a chronograph, Bullets were disassembled and cross-sectioned to fa cilitate inspection. Results: The distinguishing surface and internal features of each bullet are described, When fired into water and ordna nce gelatin, the bullets reliably expanded to 1.49 to 1.89 times their prefired diameters, Rates of kinetic energy loss of bullets of equal mass fired into ordnance gelatin were plotted. Full metal jacketed bul lets penetrated twice as deeply as deforming bullets, Jackets of some of the expanding bullets separated when fired into water. Conclusion: Expanding/fragmenting bullets produce larger, shallower wounds than do full metal jacketed bullets. Recognition of the wound and roentgenogr aphic appearances of these unusual bullets will help the trauma surgeo n to properly treat gunshot victims, Because of the occurrence of jack et separation in water, ordnance gelatin should be used for optimal ev aluation of bullet performance.