Indian homemade firearm--a technical review

Force and Sound Pressure Sensors Used for Modeling the Impact of the Firearm with a Suppressor

In this paper, a mathematical model for projectiles shooting in any direction based on sensors distributed stereoscopically is put forward. It is based on the characteristics of a shock wave around a supersonic projectile and acoustical localization. Wave equations for an acoustic monopole point source of a directed effect used for physical interpretation of pressure as an acoustic phenomenon. Simulation and measurements of novel versatile mechanical and acoustical damping system (silencer), which has both a muzzle break and silencer properties studied in this paper. The use of the proposed damping system can have great influence on the acoustic pressure field intensity from the shooter. A silencer regarded as an acoustic transducer and multi-holes waveguide with a chamber. Wave equations for an acoustic monopole point source of a directed effect used for the physical interpretation of pressure as an acoustic phenomenon. The numerical simulation results of the silencer with different configurations presented allow trends to be established. A measurement chain was used to compare the simulation results with the experimental ones. The modeling and experimental results showed an increase in silencer chamber volume results in a reduction of recorded pressure within the silencer chamber.

A quite rare case of bruising abrasion-like as gun entry wound

An interesting case of a suicide by a home made gun is described. A review of the literature is added. The entry wound is exceptional. The case shows that the forensic assessment of a home made gun case may be very difficult and implies to evaluate all the circumstances related to it. Specific forensic signs of home made gun injuries are suggested.

Penetrating cardiac injury: sustaining health by building team resilience in growing civilian violence

Penetrating cardiac injury (PCI) is gradually increasing in developing countries owing to large-scale manufacturing of illegal country-made weapons. These injuries are associated with significant morbidity and mortality. Logistically it is difficult to have all organ-based specialists arrive together and attend every critically injured patient round-the-clock in developing countries. It is therefore important for doctors (physicians, surgeons and anaesthetists) to be trained for adequate management of critically injured patients following trauma. We report the approach towards 2 cases of haemodynamically unstable PCI managed by a team of trauma doctors. Time lag (duration between injury and arrival at hospital) and quick horizontal resuscitation are important considerations in the treatment. By not referring these patients to different hospitals the team actually reduced the time lag, and a quick life-saving surgery by trauma surgeons (trained in torso surgery) offered these almost dying patients a chance of survival.

The identification of two unusual types of homemade ammunition

Illegal homemade ammunition is commonly used by criminals to commit crimes in Taiwan. Two unusual types of homemade ammunition that most closely resembling genuine ammunition are studied here. Their genuine counterparts are studied as the control samples for the purpose of comparison. Unfired ammunition is disassembled, and the morphological, dimensional, and compositional features of the bullet and cartridge case are examined. Statistical tests are employed to distinguish the dimensional differences between homemade and genuine ammunitions. Manufacturing marks on head stamps of the cartridge case are carefully examined. Compositional features of propellant powders, primer mixtures, and gunshot residues are also analyzed. The results reveal that the morphological, dimensional, and compositional features of major parts of the ammunition can be employed to differentiate homemade cartridges from genuine ones. Among these features, tool marks on the head stamps left by the bunter can be used to trace the origin of ammunition.

Country made scare gun vs. air gun--a comparative study of terminal ballistics using gelatine blocks

Country made scare gun also called as bandook in the vernacular language designed with an intention of scaring away the menacing animals is not only unique and effective but also potentially lethal and has found wide spread usage in the rural parts of India. Here an attempt has been made to study the characteristic features such as physical dimensions, mechanism of action of this weapon and to compare its penetrating ability with that of air gun, whose potential lethality is a well-documented fact, using the ballistic gelatine blocks at various ranges. It is hoped that keeping the existence of such firearms in mind by the forensic experts might help to solve the unexplained and bizarre firearm injuries encountered in day to day practice.

Self-constructed shooting devices utilizing manually-impacted firing-pins (suicide machines)

Three cases of suicide are described where deaths were due to single gunshot wounds to the head from self-constructed shooting devices. The victims were twin brothers aged 27 years, and a 53-year-old male. The firearms were manufactured by the victims who used machined metal tubes with 12-gauge shotgun and 7.65 mm ammunition, respectively. The mechanism of action in all cases relied upon direct impact on the firing pin rod; with a hammer in 2 cases, and a rock in the third. Homemade firearms are manufactured globally for use in criminal activities, although they tend to be found more often in countries and among groups where there is limited access to commercially manufactured weapons due to economic or legal constraints. Most devices use either a standard sprung hammer or trigger mechanisms. Given the unusual and cumbersome nature of the firing mechanism in the reported cases, it is likely that these firearms were specifically manufactured for the purpose of suicide.