Expansion (mushrooming) of 9 mm luger calibre jacketed hollow point bullets during penetration of a water obstacle

The firing of a shot by an officer in a public place, during an operation to apprehend a criminal, involves the risk of shooting bystanders in dynamic situations, which can occur in public places or in flats and homes. Therefore, it is important to reduce the likelihood of such situations, and therefore the development of a bullet design with a penetration depth of about 30 cm (in ballistic gelatine) and a reduction in ricocheting was initiated. The aim of this article was to find whether the size and shape of the air void in a JHP bullet design determines the size and manner of expansion. In this article, the authors presented the design of such bullets, discussed the principle of operation and conducted a ballistic experiment on the behaviour of JHP bullets in a denserthan- air environment. The chosen method (ballistic experiment) allowed the authors to obtain results on the expansion of such bullets, provided information on energy transfer or the mode of penetration (movement of the bullet) in a denser-than-air medium. The choice of JHP-type bullets used in the study was limited due to the availability of a commercially available range.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).