The article presents data based on the results of experimental studies on the external ballistics parameters and the nature of changes in the trajectory of the kinetic energy of four types of pistol cartridges bullets 9 × 21 IMI (9 × 21 mm.), which were shot from two samples of carbines with different lengths of the rifled part of the barrel.
Of particular interest are data on the nature of the shell interaction and expansive bullets of cartridges of the indicated caliber with the tissues of a biological object, the imitation of the interaction with which was carried out using ballistic testing backing material (ballistic clay). The use of a simulator of biological tissues of the human body made it possible to determine the features of the shock-contact interaction of shell and expansive bullets with them, as well as to establish the nature of the behavior of these bullets in the thickness of a viscoelastic medium. It was experimentally found that under certain conditions, 9 mm jacketed bullets are capable of inflicting through wounds to the human body at firing distances up to 25 m inclusive, while the bullet, after breaking through the barrier, has energy characteristics that are sufficient to inflict a penetrating injury of varying severity on another biological object. Due to the use of ballistic clay, it became possible to visualize the maximum amount of damage caused by shell and expansive bullets, as well as to determine the features of the formation of exit wounds, taking into account the destabilization of shell bullets in the thickness of the obstacle.
It should be noted that at firing distances up to 5 m inclusive, shell bullets, due to the loss of gyroscopic stability in the tissues of a biological object, which have a sufficiently large thickness, are capable of inflicting wounds, the volume and severity of which are comparable to or exceed the corresponding parameters of wounds caused by expansive bullets.
The obtained results of measurements of the velocity of the of shell bullets after overcoming an obstacle in the form of a viscoelastic medium can later become the basis for calculating the contact speed of a bullet with a known length of the channel of the inflicted wound. The article for the first time presents the calculated data on the parameters of the flight path of shell and expansive bullets of pistol cartridges 9 × 21 IMI (9 × 21 mm.) at firing distances up to 100 m. The presented results of experimental studies and calculated data will allow experts in the field of forensic ballistics and forensic medicine to solve the tasks set by the pre-trial investigation authorities.
Key words: ballistic clay, biological object, elements of the trajectory of a bullet flight, carbine, pistol cartridge, wound, wound channel, damaging properties, damage.
The gasoline vapors spread from “small” spills in an urban environment at low wind speeds
