Considerable debate exists among police and military professionals regarding the differences between conventional configuration weapons, where the magazine and action are located ahead of the trigger, and bullpup configuration, where they are located behind the trigger (closer to the user). To date, no published research has attempted to evaluate this question from a physical ergonomics standpoint, and the knowledge that one style might improve stability, reduce fatigue, or result in superior performance is of interest to countless military, law enforcement, and industry experts. In this study, a live-fire evaluation of both weapon styles was performed using a total of 48 participants. Shooting accuracy and fluctuations in biomechanical stability (center of pressure) were monitored while subjects used the weapons to perform standard drills. The bullpup weapon designs were found to provide a significant advantage in both respects, even while subjects showed considerable preference toward the conventional weapons. Although many mechanical and maintenance issues must be considered before committing to either platform, it is clear in terms of basic human stability that the bullpup is the more advantageous configuration.