Harrison-Gilroy’s test is a method of detecting metallic constituents in the firearm discharge or gunshot residue(GSR). This test is specific for the presence of barium, lead, and antimony in the discharge.
An explosive is a substance (an element or compound or a mixture) or device which is made to produce a volume of rapidly expanding gas in an extremely brief period of time. It is a substance which is capable of exerting pressure on its surroundings on explosion or transformation. Explosion can be defined as the rapid increase of the volume and release of high energy in a particular area due to expansion of high-energy gases. The device used to create an explosion is called an explosive. In India the definitions and rules related to explosives are described in the Indian Explosive Act, 1884. Fundamentally they are of three types i.e., mechanical, chemical and nuclear. Mechanical Explosives– A mechanical explosion requires the physical reactions to occur, which involves high-pressure gas expanding in the container beyond the tensile strength of the container and bursting it, releasing the pressure and producing shock waves. […]
A firearm is a device that hurls out the projectile with force. The force is produced by the expansion of the gases that are caused due to the burning of primer and propellant powders. Improvised firearms are generally made up of cheap quality iron tubes, sanitary pipes, and bicycle tubes, etc. Although some regular firearms may have an advanced operating mechanism, both regular firearms and improvised firearms have some parts in common, including the barrel, action, stock, and lock. This article provides information on improvised firearm and regular firearms in detail. Comparison of Improvised Firearm and Regular Firearm The ballistics of the improvised firearm and regular firearm differ in various aspects. Improvised firearms are sometimes referred to as pipe guns, zip guns, or slam guns. They are manufactured with the help of the existing materials. Improvised firearms range in standard from the crude guns that are dangerous to the user […]
Ghost guns are privately made firearms. It is a homemade firearm that lacks the commercial serial number. These terms are often used in the United States by gun control advocates, law enforcement officials, gun rights advocates. People otherwise forbidden from owning a firearm are still banned legally from the transfer, manufacture, or possession of firearms or ammunition, unconcerned of the method of manufacture or acquisition. This article provides brief information on ghost guns. How are they manufactured? Are they dangerous? Are they legal in any country? Are these guns traceable and the different ammunition used in the ghost guns? What are Ghost Guns?? These are unregulated firearms that can be bought online and can be assembled at home. Ghost guns are made by individuals using the unfinished frames or receivers containing the operating part of the firing mechanism. These are the homemade weapons– devoid of serial numbers or any other […]
Ballistics deals with the study of motions of a projectile and the factors associated with it. Ballistics experts are the individuals who perform tests on guns, spent bullets, empty cartridge cases in criminal cases to prove guilt or innocence of a suspected offender. The various ballistic evidence involves the firearm, bullet fragments, cartridge cases, cartridge clips, gun powder, different shot patterns, wads, etc., which are usually recovered from the crime scene. This article in detail describes the education qualification required to become a ballistic expert, the duties and responsibilities of a forensic expert, career aspects as a ballistics expert, and the skills required for the same. A Ballistics Expert Forensic ballistics deals with examining evidence relating to firearms and ammunition that are recovered from the crime scene. They also include analysis of the effects and behaviour of projectiles and explosive devices. “A ballistics analyst or a ballistics expert is a […]
A firearm is a device that propels out the projectile with force proceed due to the expansion of gases. Offences related to firearms are of three types that involve the homicidal, suicidal, and accidental discharge of firearm. It is the event associated with a firearm that discharges the weapon at the time that the user does not intend. Accidental discharge of a firearm occurs when there is a mechanical fault of the firearm. This kind of discharge from a firearm is produced due to the incompatibility between the firearm discharge and usages like the phenomenon of cocking off a round in a closed machine gun, mechanical malfunctions of the firearm, or due to training issues or negligence of the individuals. This article briefly discusses the accidental discharge of firearms and the factors concerned therewith. What is Meant by Accidental Discharge of Firearms??? Accidental discharge of a firearm is also known as unintentional […]
Penetration potential is the capability of the projectile to penetrate through various materials. Threshold velocity refers to the minimum velocity required by the bullets to penetrate through the skin, flesh, or bones. When the projectile strikes a human body, the skin, flesh, and bone underneath are depressed and compressed. The continued pressure stretches them beyond the elastic limit, and a hole is created. The stretched skin gains a normal state after the bullet has entered inside. The threshold velocity required to penetrate the skin is about 40-50 meters per second. Therefore, the threshold velocity value for bone penetration is 60 meters per second. The bullet continues to travel until it leaves the body through an exit hole, or its energy is spent beforehand. Wounding Effect of Projectile Depends Upon 1. The Target Site The human body is not a uniform medium. It consists of 80% water. At places, there are […]
Ballistic is the study of the motion of the projectiles and the factors affecting them. Ballistics are primarily divided into three branches internal, external and terminal ballistics. If the target is living tissue, it is known as wound ballistics. Wound ballistics is concerned with the wounding phenomena. It studies how a projectile creates a wound and causes tissue destruction by its movements on and after entering the body, its travel and then exit from the body unless it is retained in the body. Measurement of wound ballistic parameters gives qualitative ideas of firearm injuries inside the victim’s body. Various Parameters of Wound Ballistics Entry Hole– Its inverted margin usually recognizes it, the presence of scorching, blackening, tattooing, dirt ring, size, and the number of entry holes. This helps in determining the direction from which the bullet was fired. Exit Hole– It is usually recognized by the absence of various marks […]
The gunshot residue is the unburnt or half-burnt particles discharged from a firearm. Collection of gunshot residue can be done in numerous ways. Gunshot residue is also termed as firearm discharge residue and gunfire residue. Gunshot residue is usually formed when a weapon or a firearm is discharged. The vapors released by the primers are solidified into particles and adhere to people or objects around. GSR particles greatly vary in shape and size, and hence the examiner must collect and analyze all types of particles found so that they won’t miss out on any evidence. The quantity and quality of the GSR particles are affected by various factors such as the type of the gun, caliber, bullet, the burn rate of the powder charge, and the environmental condition. Sources of Gunshot Residue The most primary source of gunshot residue is the primer and the propellant. It also consists of the […]
The theory of recoil is based on Newton’s third law of motion. Newton’s third law of motion states there is an equal and opposite reaction for each action. The recoil of a gun is defined as the rearward or the backward motion of the gun in reaction to the forwarding motion imparted to the projectile and propellant gases. The recoil caused by the gun balances the forward momentum of the projectile and exhaust gases. The various concepts involved in the theory of recoil, including the factors affecting the recoil, are discussed in the article. The theory of recoil, in technical terms, is the result of the conservation of momentum. The forward momentum gained by the projectile and gases is accompanied by an identical gain in the rearward momentum of the gun. The speed of the recoil system of a gun is low compared to the muzzle velocity. Factors affecting the recoil […]
The cartridge is the entire pre-assembled firearm packaging referred to as a bullet. The bullet is a projectile that’s housed inside a cartridge. Ammunition is a cartridge composed of shells, propellant, primer, and projectiles commonly used in firearms. The standard ammunition comprises the following basic components: Cartridge Case, primer and primer cap, powder or propellant, wads, and the projectile. This article further deals with the various components of the cartridge in detail. Cartridge Case of Bullets A cartridge case is also known as the shell after its contents are discharged. It provides housing for various components of the cartridge. It is usually made up of brass for rifle, pistol, and revolver ammunition. For shotgun, it is made up of several layers of thin paper, which are tightly compressed. The base of the paper shell is made up of brass. Plastic shells are also manufactured. Cartridge cases are classified into three major groups based […]
Bullets fired through rifled firearms receive both the class and individual characteristics of the barrel from which they are fired. These random and class characters define the characteristics of bullet. The bullet show the primary markings left behind by the gun barrel’s lands and grooves and reveals the fine striations on all marks. The various class characteristics of bullet include caliber, number of lands and grooves, twist direction, and width of the lands and grooves. Individual characteristics of the bullet include the striation marks present on the bullet. This article further explains in detail the various class and individual characteristics of bullets. Class Characteristics of Bullets Class characteristics of physical evidence are always referred to the properties which can be associated only with a group and not with a single source. The following are the characteristic of bullets which can be classified under the class characters. 1. Number of Lands […]
A shotgun is a firearm that has a design similar to that of the rifle. The difference lies in the barrel, ammunition, and purpose. The shotgun has a smooth barrel and the ammunition used are shots that contain metal pellets that spray around when shot. Choking in shotgun firearm is defined as a constriction to the shotgun’s bore at the muzzle end. A shotgun choke can make a significant difference to the shooting. This article describes in detail the chocking in shotgun firearms. Choking in Shotgun Firearms On firing shotshells from the shotgun, the pellets leave the barrel and then spread. The farther the pellets travel, more the pellets are spread. This spread of pellets is known as a shot string. Barrels of shotgun consists of choke that helps control the shot string. Chokes are either formed by squeezing the end of the bore or by threading the barrel and fixing an […]
What is a shoulder gun?? Shoulder guns are firearms that are fired with the gun held in hands and the butt of the weapon braced against the shoulder. These are heavy guns that require both hands to aim accurately. Shoulder firearms are grouped into two categories that are shotguns and rifles. The difference between shotguns and rifles lies in the design of the barrel. Shoulder guns with a barrel having lands and grooves are rifles, while that of a shotgun has a smooth barrel. Shotguns have single and double-barreled configurations. All shoulder guns have three basic parts which are action, stock, and the barrel. The parts of the shoulder guns with their functions are discussed in the article. Breakdown of Basic Components of Shoulder Guns Conclusion The shoulder gun comprises of three significant parts. Those parts include action, barrel, and stock. The various other components present in the shoulder gun have their […]
Small arms, often referred to as firearms, are man-portable lethal weapons for individuals to use that can expel or launch a shot, bullet, or projectile by the action of explosion. Small Arms include revolvers, pistols, and long guns, namely rifles, assault rifles, submachine guns, etc. firearms that consist of several parts. The standard components of small arms include a barrel, a magazine, handguard, pistol grip, trigger, and trigger guard. The three primary groups of parts included in almost all firearms are action, stock, and barrel. Action: The part of a firearm that includes all the moving parts that load, fire, and eject out the cartridge cases. Stock: A wood, metal, or plastic frame that holds the barrel and action and allows the gun to be held firmly. Barrel: The metal tube that is bored out provides an exit path for the discharging projectile, which is either rifled or smooth. Breakdown […]
