FORENSIC BALLISTICS (Note)
1. Internal = before leaving the muzzle, while inside the barrel,
From breech to muzzle.
2. External = before reaching the target, upon leaving the muzzle, while in flight, from muzzle to target.
3. Terminal = upon reaching the target.
4. Forensic Ballistics = science of Firearms Identification. Identification & Investigation of ammunition &
firearms.
(Col. Calvin H. Goddard = Father of Ballistics)
Trigger – hammer – firing pin – primer – gunpowder.
Percussion action = ignition of priming mixture.
Alexander John Forsyth
Firearms = (Sec. 877,RAC)
P.D. 1866
R.A. 8294.
1. Artillery = more than 1 Inch
2. Small Arms = Less than 1 inch
Machine Gun = automatic/ continuous firing.
Sub-machine gun (grease gun)
Shoulder Arm
Smooth bore = musket (ancient/muzzle loading)
Shotgun (breech loading/ a number of lead pellets.
Cylinder type = equal diameter
Choke = reducing diameter
Paradox = with rifling a few inch from the muzzle point.
Rifles Bore = Rifle (with rifling)
Carbine = short barrel rifle, less than 22 inches.
Hand gun = Pistol ; Revolver (cylinder)
Single action = manual cocking
Double Action = both cock and release the hammer.
Barrel of any firearm is a complete firearm.
Kolibre = smallest pistol
Zip gun = home made gun
Freakish gun = a tool to which a firearm mechanism is attached.
Tool gun= looks like a firearm.
Single shot= one firing for every loading; chamber feed.
Repeating arms = several shot for very press of the trigger.
Automatic = continuous firing in a single press.
(cartridge is found at the scene of firing).
Ammunition = loaded shell
Dummy = fake
Blank = without bullet.
Drill = without gun powder.
Live = complete unfired unit (Cartridge)
Shotgun Cartridge = consists of pellet, wads, shell, gunpowder and primer.
Cartridge = consists of bullet, shell, gun powder and primer.
Cartridge (Latin= charta “paper”; French “Cartouche” = rolled paper.)
Four classes of cartridge according to type of firearms: (revolver, pistol, rifle & shotgun)
Parts of the Cartridge
1. Bullet ( French “Boulette” ) = a small ball.
Metallic or non-metallic ball propel from a firearm.
3. Cartridge case = tabular container.
4. Gun powder or propellant or powder charge.
Black powder = 75% KNO3, 15%Charcoal,10%Sulfur.
Smokeless= Nitrocellulose, nitroglycerine
5. Primer = ignition system.
Priming mixture = KCLO3, Charcoal & Sulfur.
Classes:
Rim-fire = powder is located at the cavity rim.
Center-fire = powder is located at the center cap.
Pin-fire = with built-in pin. (obsolete already)
1. Rimmed type = the rim diameter is greater than the body diameter.
2. Semi-rimmed = “slightly greater”
3. Rimless = Rim D. is equal to the Body D.
4. Rebated = Rim. D. is smaller than the Body D.
5. Belted = with metal belt around the body of the shell used in high power gun such as shotgun.
Bullet = metallic or non-metallic ball propel from a firearm. (usually fired from small arms).
Shot = other name for bullet.
Slugs = police term for bullet.
Pellets = used in shotgun.
Missile = usually used in artillery firearm.
1. Ball type = for personnel
Lead (revolver) jacketed ( outer covering is jacket)
2. Armour Piercing = for metallic target.
3. Incendiary = used to set fire. (Blue –tip)
4. Tracer = emits a bright flame, used at night. (red-tip)
5. Explosives = designed for explosion.
Expanding Bullet = hallow point and the Soft-point. Also called mushroom bullet.
Dum-Dum = made in India for greater damage.
Baton Round = anti-riot bullet. Also called rubber bullet.
Discarding Sabot (Accelarator bullet)= designed for greater velocity.
Frangible = paint bullet.
Explosives
1. Low Explosives = those which function but burning producing gases. (Gunpowders)
2. High Explosives =
a. Primary High = those which ignites upon friction or shock (priming mixture).
b. Secondary High = those which explodes (TNT Dynamite, DRX, C-4 and Nitrogylcerine liquid bomb)
Caliber = measured with the used of a caliper or micrometer.
Firearms = Bore diameter (distance from two opposite lands).
Bullet = base diameter
Shell = body diameter
Torsion balance = use to measure caliber of bullet based on weight.
Pitch of Rifling = distance in one complete turn of the bullet. (measured by Helixometer)
Velocity = speed by unit of time (ft/sec) . Measured by Chronograph.
Class Characteristics = determined even before the manufacture.
Individual Char. = determined after the manufacture .
Rifling = helical groove inside the barrel.
Steyer = 4RG=L
Smith and Wesson = 5RG=L
Colt = 6LG2X
Browing = 6RG2X
Striation marks = minutes scratches.
Shaving marks = due to poor alignment.
Skid mark = due to forward movement before it rotates.
Stripping = due to worn-out barrel (corrosion/Erosion)
Slippage = due to oily or oversized barrel.
Class characteristics = common or found in others.
Individual char. = peculiar or not found in other f/a.
Ballistics Engineer/ Firearms Examiner/ Ballistician = concerns with weapons and projectile.