ELECTIVE I: FORENSIC PHYSICAL SCIENCES (FACT & FACT Plus 2022)

Forensic Ballistics

a) Firearms and Ammunitions, their classification, details of various small arms used in crime – shotguns, rifles, revolvers, pistols, carbines, improvised firearms.

Bore and caliber, choke, automatic mechanisms employed in small arms, rifling – class characteristics of rifled bore, purpose of rifling, types of rifling, methods to produce rifling, various locks used in small arms. Head-space.

Various types of primers/ priming mixtures, propellants, shotgun ball ammunition, various kinds of bullets, head-stamp markings. Various physical, ballistic & functional tests of ammunitions.

b) Physical evidence and other clues Handling of evidence, various precautions.

c) Internal Ballistics: Ignition and burning of propellants, degressive and progressive powders, rate of burning propellants, factors affecting internal ballistics of projectiles, internal ballistics of 12-bore guns, recoil.

d) External Ballistics: Equations of motion of projectiles, principal problem of exterior ballistics, vacuum trajectory – calculation of various elements, effect of air resistance on trajectory, points of difference between trajectories in air and vacuum, nature of air resistance phenomena, base-drag, yaw, cross-wind force, overturning moments, stability – fin stabilization and gyroscopic stability, stability factor, nutation and precessional motions of bullets, drift, Magnus effect, Greenhill formula, shape of projectile – form factor, ballistic coefficient, calculation of trajectories of various small arm bullets, calculation of trajectories of shotgun projectile, use of ballistic tables, projectile velocity determination, determination of velocity of shot-charge, Doppler-radar method. Automated system of trajectory computation. Falling bullets – limiting velocity, drop, use of lead as bullet material.

e) Terminal Ballistics: Interaction and penetration of various smallarm projectiles in various tissues. Threshold velocity for penetration of skin, flesh and bones, threshold energy/ casualty criteria, energy density, ricochet, various aspects of wound ballistics including wounds of entrance/ exit/ track of projectile, gunshot injuries caused by different types of firearm ammunitions. Temporary and permanent cavities, materials simulating human body, gunshot wound as a function of shape of nose of bullet, striking velocity, nature of target, tumbling of bullet, effect of instability of bullet, effect of intermediate target. Influence of range, identification of gunshot injuries, motion of projectile in dense medium.

f) Class and Individual characteristics of fired bullets and cartridge cases and their linkage with the suspected firearms, comparison microscope, photomicrography, source correspondence, linkage of fired shots with shotguns.

g) Determination of range of firing in cases of firing by smooth-bore and rifled firearms, factors affecting range of firing, stringing of shots, effect of string on pattern, Cart-wheel pattern, balling, Walkers’ Test, IR photography.

h) Chemical tests for examination and identification of shotgun holes in various targets. Gunshot residue. Identification of shooter.

Scientific methods of shooting reconstruction, suicide, murder, accident, self-defense and encounter cases. – medico-legal report, basic ballistic facts, laboratory examination reports, Documentation and evaluation of bullet holes in various materials, ricochet marks, pellet pattern in various targets

i) Instrumentation techniques – AAS, NAA, SEM/EDXA, ICP-MS, ASV and their application in ballistic examination.

j) Arms Act and Arms Rule, 2016.