Forensic Ballistics: Bullet, Cartridge and Shell Examination

Medium-band UGC-NET Forensic Science Paper II Unit V drill on bullet, cartridge case and shell examination. The set covers rifling characteristics in detail (number of lands and grooves, twist direction left or right, twist rate notation such as 1 in 10 inches, groove width and depth, caliber from land-to-land diameter), and the four principal rifling manufacturing methods (broaching, button rifling, hammer forging on a mandrel, and electrochemical machining) along with polygonal versus conventional rifling profiles. Cartridge case toolmarks are examined under the comparison microscope: breech-face machining patterns (parallel milling versus circular turning), hemispherical versus elliptical firing-pin impressions, firing-pin drag and aperture shear, extractor marks on the rim and ejector marks on the case head with their location conventions, magazine lip marks and chambering marks on the case body. The mock then moves to the integrated ballistic identification systems used in casework worldwide: IBIS BrassTRAX and BulletTRAX from Ultra Forensic Technology, the ATF-administered NIBIN national network in the United States, the Evofinder 3D correlation platform, and the ANCIBE Indian indigenous ballistic identification project rolled out across CFSL laboratories. The AFTE Range of Conclusions (Identification, Inconclusive A, B, C, Elimination, Unsuitable for examination) is covered with the consecutive matching striae (CMS) decision criterion. Indian CFSL casework wraps up the set: BNSS 2023 receipt of the firearm and case property, test firing into the water tank or cotton-box recovery system, comparison microscope examination, and the BSA 2023 Section 39 expert report with chain-of-custody documentation. The cited authorities are Brian Heard's Handbook of Firearms and Ballistics, Saferstein, Sharma B.R., Warlow, and the AFTE Theory of Identification and Glossary.

Aimed at UGC-NET Forensic Science Paper II aspirants targeting Unit V (Forensic Ballistics, Toolmarks and Explosives), NFSU MSc Forensic Science students preparing for ballistics laboratory rotation, FACT aptitude candidates, and serving Indian state-CID and CFSL trainees who need to align casework practice with examination expectations. Several questions are written in the applied-scenario style now favoured by UGC and NFSU, where the candidate has to choose the correct procedure or interpretation under realistic constraints.

Topics covered:

• Rifling: lands, grooves, twist direction, pitch, caliber measurement
• Rifling manufacturing: broaching, button, hammer forging, ECM, polygonal
• Breech-face and firing-pin marks on the cartridge head
• Extractor and ejector marks on the cartridge case
• IBIS, NIBIN, Evofinder and ANCIBE ballistic databases
• AFTE Range of Conclusions and consecutive matching striae
• Indian CFSL workflow: BNSS receipt, test firing, BSA Section 39 report
• Comparison microscopy and chain of custody in Indian casework

Sit it in one go, treat distractors as near-twin alternatives, and revisit every wrong answer against the cited Heard, Saferstein, Sharma and AFTE references before moving on. Allow 30 minutes.