Forensic Ballistics: Foundations and Core Vocabulary

This easy-level mock covers the foundational vocabulary, core concepts, and essential principles of forensic ballistics that every NFSU MSc and FACT candidate must master before approaching application-level material. All thirty questions are pitched at the definitional level.

Questions cover: rifling definition (helical grooves + spin stabilisation + marks on bullet), calibre as barrel internal diameter (measured between lands; inches or mm), the four cartridge components (case + primer + propellant + projectile), the firing sequence of a semi-automatic pistol (trigger → firing pin → primer → propellant → projectile → recoil → extract → eject), GSR composition (Pb + Ba + Sb spherical particles from primer; SEM-EDX analysis), hard-contact entrance wound features (searing + muzzle imprint + stellate tearing over bone), the three domains of ballistics (internal, external, terminal/wound), shotgun gauge definition (number of bore-diameter lead balls per pound), shotgun choke (muzzle constriction controlling shot spread), striations as individualising bullet marks (comparison microscopy), entrance wound in soft tissue (abrasion ring + inverted margins + smaller than exit), lands and grooves definition (raised ridges and recessed channels in rifled barrel), wound/terminal ballistics definition (energy transfer + cavities + tissue damage), firing pin impression as individualising case mark, stippling/tattooing (powder grains embed at intermediate range; cannot be wiped), IBIS as digital candidate-list search tool (analogous to AFIS), FMJ vs hollow-point bullet (jacketed penetration vs expanding cavity), internal ballistics (inside barrel from primer to muzzle exit), semi-automatic vs fully automatic (one pull one round vs continuous), test fires for comparison (individualising marks → identification/exclusion), temporary cavity (kinetic energy pressure wave; more with high-velocity rounds), powder fouling (carbon residues indicating recent discharge), shotgun shot pattern for range estimation (wider spread = greater distance), breech face mark (pressure impression links case to specific firearm), bullet jacket functions (prevents leading + allows high velocity + FMJ military), recent discharge indicators (fouling + smell + nitrite test), Indian Arms Act licencing requirements (District Magistrate licence; unlicensed possession offence), extractor vs ejector functions (extractor withdraws + ejector flips out), shotgun wad functions (gas seal + shot protection + pattern control), and back spatter at contact wounds (gases expel blood back through entrance toward shooter).

Topics covered:

• Firearm types and components: rifling, calibre, gauge, choke, semi-auto vs fully automatic, extractor, ejector
• Ammunition: cartridge components (four), FMJ vs hollow point, bullet jacket, wad in shotgun shell
• Forensic marks: striations, breech face mark, firing pin impression, lands and grooves, GSR
• Wound science: entrance vs exit wound, contact wound features, stippling, temporary cavity, back spatter, wound ballistics
• Ballistics divisions: internal, external, terminal (wound)
• Operations: test fires, IBIS, recent discharge indicators, Indian Arms Act

Each question cites Saferstein's Criminalistics 13th edition. Allow 30 minutes.