Testing Ballistic Dispersion When the Aim Point Is Unknown

Abstract

In this paper, we point out a fundamental error in the procedures used to measure ballistic dispersion. We argue that there are two components to a proper measure of dispersion: i) dispersion arising from the ‘unknown’ aim point and ii) dispersion caused by the cloud, which can be measured directly from the sample mean point of impact. The procedures currently in use only take into account the cloud dispersion, and thus, underestimate the actual (total) dispersion. These procedures fail to recognize the existence of the fixed ”aim point”. As a result, incorrect conclusions may be drawn. An elementary correction to the underlying statistics corrects this error when the fall of shot follows a circular normal distribution.