Method for establishing the presence of a ricochet and determining the bullet's angle of impact with the barrier depending on the characteristics of entry bullet gunshot wounds

Abstract

The article presents some results of its own experimental study on the basis of which are given the possibility of experimental modeling ricochet bullets, developed a method of determining the existence of ricochet in entrance gunshot damages of biological and non-biological targets resulting from the firing of the 9mm Makarov pistol containing regression model according to the interval values of the bullets incident angle with the barrier on three parameters of this type of gunshot wounds and the adjoining areas. Resulting from the use of this method is the formation of an objective justification to establish the circumstances of the incident with said sample of firearms. In the introduction of scientific articles are presented as the most significant achievements in the field of forensics of gunshot injuries, and aspects that require further study; argued the relevance of the research topic chosen by the author, given its purpose and objectives. In the «Material and methods» explains how to conduct their own pilot study on the formation of gunshot injuries of biological and non-biological targets, resulting from the firing of 9mm Makarov pistol, are detailed conditions and parameters of the laboratory experiment, shows a list of scientific research methods that have been applied for the study of gunshot injuries experimental targets. In the «Results and discussion» stages of the study are the author formed during the experiment gunshot injuries of biological and non-biological targets disclosed technique used, the calculated values obtained are specified boundaries 99% confidence intervals for the mean values of quantitative parameters of damage depending on the target ( biological, non-biological), the ricochet incident angle (10–20° or 30–50°), for determining the set of their characteristics gunshot injuries inherent for different values of the angle between the bullets with an obstacle, types of obstacles and objects falling bullets after the bounce, describes a mechanism Education site wiping the edges of the input bullet fire damage set the parameters for a given trait, depending on the ricochet incident angle (10–20° or 30–50°); above-stated study design values borders 99% confidence intervals for the mean values of quantitative parameters of damage, as well as the presence and site parameters wiping the edges of the input bullet fire damage to allow you to set «Ricochet» nature of gunshot injuries. At the end of this section, the author gives them developed using logistic regression model, which allows to predict the range of on the ricochet incident angle depending on the range (10–20° or 30–50°), which is based on the classification accuracy for non-biological target is 88,0%, and for non-biological — 84,2%. In the «Conclusions», the author briefly summarizes the obtained results of the study and recommendations on possible causes of their application in practice in order to establish the circumstances of the accident with a firearm.