Wounding effects of the AK-47 rifle used by Patrick Purdy in the Stockton, California, schoolyard shooting of January 17, 1989

The limited disruption produced in tissue simulant by the rifle and bullets used in the Stockton, California, schoolyard shooting is entirely consistent with the autopsy reports on the five children who died of their wounds. It is also entirely consistent with well-documented battlefield studies and with previous tissue-simulant studies from many laboratories. It is inconsistent with many exaggerated accounts of assault-rifle wounding effects described by the media in the aftermath of this incident. This information should be documented for the historical record. However, the critical reason for correcting the misconceptions produced by media reaction to this incident is to prevent inappropriate gunshot-wound treatment.     

Velocity necessary for a BB to penetrate the eye: an experimental study using pig eyes

PURPOSE: To determine the V-50 threshold velocity needed for a steel BB to penetrate the eye of a 230-pound pig. METHOD: BBs were shot at a distance of 10 feet into the corneas of pig eyes with a pump-action BB gun. RESULTS: The V-50 velocity for corneal penetration and serious disruption of the eye was found to be 246 ft/sec. CONCLUSION: Due to the nearly identical size and anatomy of the human eye to the pig eyes used in this study, it is felt that 246 ft/sec is a reasonable approximation of the velocity needed to penetrate the human eye.     

Ordnance gelatin for ballistic studies. Detrimental effect of excess heat used in gelatin preparation

Most users of ordnance gelatin for ballistics studies are apparently unaware of the detrimental effects on this tissue simulant's properties caused by excess heating in reconstitution of the gelatin powder. Material published by the Gelatin Manufacturers Institute of America states that heating gelatin above 40 degrees C can be detrimental to its properties. The manufacturer of type 250 A Ordnance Gelatin does not include directions for preparation with the gelatin powder. Directions that can be obtained by contacting the manufacturer fail to give any recommendations on the amount of heat applied during gelatin preparation and do not mention the detrimental effects of excess heat. These oversights are corrected in the revised set of directions included in this article.