Forensic Ballistics
Forensic Ballistics Quiz Crafted by -
Dr. Pragnesh Parmar
Professor and Head
Department of Forensic Medicine
GMERS Medical College, Vadnagar, Gujarat, India
Introduction to Forensic Ballistics
A ballistics expert understands the different marks that firearms leave on bullets when they are fired, including the marks of the rifling on a barrel and other striations on the projectile. They may also perform modeling of the scene to identify where a firearm or explosive was used and perform chemical analysis to identify the weapon that was used. Ballistics experts frequently display graphics, video, or other explanations of the results of their analysis in court. Forensic ballistics experts typically work in crime labs for local governments, state governments, or the federal government, including such organizations as the Federal Bureau of Investigation (FBI). Other experts offer private consulting services.
Here is the List of Questions with Answers along with explanation
Que 1. Choking in a firearm
A. Increases the speed of the bullet
B. Is constriction of the terminal part of the muzzle end
C. Is constriction of the proximal part of the breech end
D. Means that the bullets are stuck inside
Answer: B) Is constriction of the terminal part of the muzzle end
Explanation: In firearms, a choke is a tapered constriction of a gun barrel at the muzzle end. Chokes are most commonly seen on shotguns, but are also used on some rifles, pistols, or even air guns. Chokes may be formed at the time of manufacture either as part of the barrel, by squeezing the end of the bore down over a mandrel, or by threading the barrel and screwing in an interchangeable choke tube. Chokes may also be formed even after a barrel is manufactured by increasing the diameter of the bore inside a barrel, creating what is called a "jug choke", or by installing screw-in chokes within a barrel.
Que 2. Lands and Grooves inside the barrel of a firearm help to
A. Narrow down the spread of pellets
B. Impart spin to the pellet
C. Increase the cosmetic appearance of the firearm
D. Identify make of the firearm after examining the projectile
Answer: D) Identify make of the firearm after examining the projectile
Explanation: Lands are the raised portions between the grooves inside the barrel after the spiral grooves are cut to produce the rifling. Rifling: The spiral grooves cut or swaged inside a gun barrel that gives the bullet a spinning motion. The metal between the grooves is called a "land". Thus, the lands and grooves inside the barrel of a firearm help to identify make of the firearm after examining the projectile.
Que 3. Entrance wound of a rifled firearm shot from distant range is characterized by
A. Only inner grease collar and outer abrasion collar
B. Singeing of hairs around the wound
C. Tattooing of the adjacent skin
D. Everted margins
Answer: A) Only inner grease collar and outer abrasion collar
Explanation: When the muzzle to skin distance is beyond the range of powder deposition, circular defects are seen with an abraded rim, but with no associated searing, soot deposition or powder tattooing. The abrasion rim may be missing where skin overlays a bony support (Besant-Matthews 2000).
Distant shots from rifles may result in a central defect with micro tearing of the wound edges, and massive internal destruction.
Que 4. Black powder used as propellant in the firearms contains
A. Charcoal, potassium nitrate and nitrocellulose
B. Charcoal, potassium nitrate and nitroglycerine
C. Charcoal, potassium nitrate and sulfur
D. Charcoal, nitroglycerine and sulfur
Answer: C) Charcoal, potassium nitrate and sulfur
Explanation: The black powder consists of charcoal (carbon), saltpeter (potassium nitrate or sometimes sodium nitrate), and sulfur. Charcoal and sulfur act as the fuel for the explosion, while saltpeter acts as an oxidizer. Sulfur also lowers the ignition temperature, which increases the combustion rate.
Que 5. A ricochet bullet is the one that
A. Explodes on hitting the target
B. Hits an unintended target after hitting the primary target aimed at
C. Hits an intermediary target, gets deflected and then hits the primary target aimed at
D. Hits an intermediary target, gets deflected and then hits the unintended target
Answer: D) Hits an intermediary target, gets deflected and then hits the unintended target
Explanation: When a bullet strikes any surface, there is a critical angle at which the bullet will bounce off or ricochet from the surface rather than penetrate. After ricocheting from the surface, the missile will lose a considerable amount of its velocity (anything up to 35% in test firings) and, invariably, lose its stability. This is contrary to the popular belief that a ricocheting bullet will carry further than one fired at the elevation for maximum range.
The actual degree at which a bullet will ricochet from a surface is called the critical angle. Predicting this critical angle for any bullet/surface configuration is, however, extremely difficult. Factors such as bullet shape, construction, velocity and ricocheting surface all have a pronounced effect on the outcome
Que 6. The bullet whose nose is sawn off and mushrooms out on hitting the target is known as
A. Frangible bullet
B. Ricochet bullet
C. Dum Dum bullet
D. Tandem bullet
Answer: C) Dum Dum bullet
Explanation: In the 1890s, the British military developed a bullet to be used at Dum Dum arsenal in India's North-West frontier and was named 'dumdum' bullet. It comprised a jacketed .303 bullet in which the jacket nose opened to expose its lead core to improve the effectiveness of the bullet by increasing its expansion upon impact. Afterwards, the term dumdum was taken to include any soft-nosed or hallow-pointed bullet. In 1899, the use of dumdum bullet was outlawed following the Hague Convention. But during First World War, the Germans accused the Belgian government of having used a dumdum bullet which the Belgians strongly denied.
Que 7. Which one of the following is not a part of the shotgun cartridge?
A. Bullet
B. Cardboard wad
C. Felt wad
D. Propellant
Answer: A) Bullet
Explanation: There are five parts of a shotgun cartridge namely, a plastic (sometimes paper) case, primer, wad, and shot.
While bullet is a projectile and a component of firearm ammunition that is expelled from a gun barrel during shooting.
Que 8. Which one of the following feature is not seen at the entry wound caused by the bullet that has passed through the wearing apparel?
A. Abrasion collar
B. Grease collar
C. Circular shape of the wound
D. None of the above
Answer: B) Grease collar
Explanation: The grease carried from the barrel usually deposits round of the dirt carried by it at the entrance wound. This may not be present if the bullet has passed through the wearing apparel.
Que 9. The exit wound at the back of the victim who was killed at point blank range shows
A. Burning of the skin
B. Blackening
C. Tattooing
D. None of the above
Answer: D) None of the above
Explanation: All the features are characteristics of an entry wound which are caused at different firing range due to the carriage or expelling of soot, dirt and powder particles.
Also, "Point blank" does not mean "contact distance" as some think it means. The term point blank would describe that distance out from the muzzle which is close enough that there has been little or no practical degradation of ballistic performance. For a handgun, that might mean 4 or 5 feet, or even further depending on the caliber. For a rifle, "point blank" might mean 15 or 20 yards or more.
Que 10. Souvenir bullet is one that
A. Is embedded in the tissues for long
B. Has no penetrating power
C. Is unjacketed
D. The victim desires to keep for himself after its removal from his body, as a souvenir
Answer: A) Is embedded in the tissues for long
Explanation: Souvenir bullet is the bullet which is present in the body for a long period of time. There is no fresh bleeding in the surrounding area. A dense fibrous tissue capsule usually surrounds it.
Que 11. The composition of black powder was first recorded by English Franciscan monk Roger Bacon in year
A. 1249
B. 1349
C. 1149
D. 1449
Answer: A) 1249
Explanation: The composition of black powder was first recorded by English Franciscan monk Roger Bacon in 1249, but he did not apply it to the propulsion of a missile from a firearm. This use of black powder is usually credited to a German Franciscan monk Berthold Schwartz in the early fourteenth century.
Que 12. Development of a percussion primer was done by a Scottish clergyman, the Reverend Alexander John Forsyth, in year
A. 1805
B. 1705
C. 1875
D. 1775
Answer: A) 1805
Explanation: Alexander John Forsyth, (born Dec. 28, 1769, Belhelvie, Aberdeenshire, Scot.—died June 11, 1843, Belhelvie), Scottish Presbyterian minister and inventor who between 1805 and 1807 produced a percussion lock for firearms that would explode a priming compound with a sharp blow, thereby avoiding the priming powder and free, exposed sparks of the flintlock system.
Forsyth had faith in his invention and on April 11th, 1807 was granted a patent for his lock, using fulminate as a priming compound for firearms. The patent was so carefully worded, so as to stop anyone else from making a lock using percussion. He was successful in defending his patent on many occasions, before its expiry in 1821.
Que 13. Rifling of the bore was first applied to firearms by German gunsmith
A. Augustin Kutler
B. General J. Jacob
C. William Ellis Metford
D. Major Rubin
Answer: A) Augustin Kutler
Explanation: Rifling of the bore was found to improve the accuracy and consequently the effective range of firearms, and was first applied to firearms by German gunsmith Augustin Kutler in 1520.
Que 14. The first practical repeating firearm was a revolver manufactured in 1835 by
A. Samuel Colt
B. George Luger
C. Mannlicher
D. Dr. Richard Gatling
Answer: A) Samuel Colt
Explanation: Samuel Colt (born Hartford, Connecticut July 19, 1814 – died Hartford, Connecticut January 10, 1862) was an American inventor and industrialist. He was the founder of the Colt’s Patent Fire-Arms Manufacturing Company (now known as Colt’s Manufacturing Company), and is widely credited with popularizing the revolver gun. Colt’s innovative contributions to industry have been described by arms historian James E. Serven as „events which shaped the destiny of American Firearms.”
It was this first, that practical revolver and the first practical repeating firearm,” made possible by converging percussion technology, that would be the genesis of what would later germinate into an industrial and cultural legacy and a priceless contribution to the development of war technology; that was ironically personified in the naming of one of his later revolving innovations, the Peacemaker.
Que 15. Exit wound is characterized by all of the following except
A. Everted margins
B. Protrusion of fat
C. Tattooing at the edges
D. Wound bigger than the size of the bullet
Answer: C) Tattooing at the edges
Explanation: Tattooing is usually observed in the wounds caused in case of intermediate range. It is caused by the powder particles. Thus, found at the entry point of the wound. Other three features namely, everted margins, protrusion of fat, and wound size bigger than the size of bullet are the characteristic features of an exit wound.