Internal Ballistics
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Internal ballistics is the study of what happens inside the barrel of a firearm from the moment of ignition until the projectile exits. When fired, the projectile is accelerated to high velocity by the burning of propellant gases trapped behind it in the barrel. There are three types of propellant powders - progressive powders increase burning surface as they burn, degressive powders decrease burning surface, and neutral powders maintain a constant burning surface.
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Internal Ballistics
Internal ballistics refers to what occurs within a weapon's barrel from firing to bullet exit. Key phenomena include:
- Ignition starts when the firing pin strikes the primer, igniting propellant which burns to form high-pressure gas.
- Propellant combustion and barrel length impact velocity - short barrels require fast-burning powder while long barrels use progressive-burning powder.
- Atmospheric conditions like temperature affect ballistics, as ammunition is manufactured for a specific temperature range and velocities vary with temperature.
Introduction to Forensic Ballistics
1. Ballistics is the science dealing with the motion, impact, launching and flight behavior of projectiles. It includes interior, exterior and terminal ballistics.
2. A firearm uses an assembly of a primer, propellant and projectile(s) to generate power and discharge the projectile(s) at high velocity. Common firearms include revolvers, self-loading rifles, and shotguns.
3. A cartridge contains the primer, propellant and projectile(s) assembled into a container. It uses the energy from burning propellant gases to launch the projectile(s) down the barrel of the firearm.
Propallent burning
The document discusses different types of propellants used in ballistics and pyrotechnics. It describes various solid and liquid propellant compositions and their uses. Solid propellants can have different grain shapes that determine their burn rate characteristics, such as progressive, digressive, or neutral burns. Common shapes include flake, ball, cord, single perforation, 7-perforation, and 19-perforation grains. Liquid propellants often use combinations of fuels and oxidizers like nitric acid and kerosene or liquid hydrogen and liquid oxygen.
Internal ballistics
This document discusses the topic of internal ballistics, which deals with the motion of projectiles inside a weapon's barrel. It provides information on factors that affect muzzle velocity, such as the quantity and quality of powder, barrel length, and bullet fit. The Le Duc empirical formula is presented, which approximates the velocity-space curve of a projectile in a gun based on distance traveled. The concept of the "all burnt point", where all of the propellant has been consumed, is explained.
Internal ballistic
This document discusses the topic of internal ballistics, which is the science of what occurs inside a firearm when it is discharged. It begins with a brief history of ballistics and defines internal ballistics. Some key phenomena of internal ballistics discussed include ignition, combustion of propellants, barrel length, atmospheric conditions, the shape of cartridge cases, and heat problems during combustion. Lock time and barrel time are also defined. The document provides details on each of these topics as they relate to internal ballistics and ballistic performance.
Terminal ballistics
1. Terminal ballistics deals with the behavior and effects of projectiles when they impact targets and transfer energy. It studies penetration potential and wound ballistics.
2. When a projectile strikes the body, it compresses tissues until they tear beyond their elastic limits if the projectile has enough energy. It continues through an exit wound, causing internal damage.
3. Factors affecting wounding include the target site, velocity, projectile construction, and range. Frontal wounds cause more damage due to shallow tissue depth. Higher velocities increase energy and damage.
Internal ballistics
Internal ballistics is the study of a projectile's behavior from ignition until it exits the gun barrel. It examines factors like lock time, ignition time, and barrel time. Piobert's law states that gunpowder burns layer by layer. Newton's third law means that for every action there is an equal and opposite reaction, causing recoil. Recoil velocity can be calculated using the projectile and gun masses and velocities. Rusting and erosion over time degrade the gun barrel and reduce accuracy.
Firearm and its classification.
The document discusses the classification of firearms. It describes firearms as being classified based on their bore (smooth bore vs rifled), loading mechanism (muzzleloader, breechloader, magazine loader), action (lever, bolt, self-loading), firing capability (single shot vs repeater), how they are handled (handguns vs shoulder arms) and their use (service vs sporting). Primitive firearms discussed include matchlock, wheel-lock, flintlock and muzzleloaders. Modern firearms are classified based on these various characteristics.
Recommended
Internal Ballistics
Internal ballistics refers to what occurs within a weapon's barrel from firing to bullet exit. Key phenomena include:
- Ignition starts when the firing pin strikes the primer, igniting propellant which burns to form high-pressure gas.
- Propellant combustion and barrel length impact velocity - short barrels require fast-burning powder while long barrels use progressive-burning powder.
- Atmospheric conditions like temperature affect ballistics, as ammunition is manufactured for a specific temperature range and velocities vary with temperature.
Introduction to Forensic Ballistics
1. Ballistics is the science dealing with the motion, impact, launching and flight behavior of projectiles. It includes interior, exterior and terminal ballistics.
2. A firearm uses an assembly of a primer, propellant and projectile(s) to generate power and discharge the projectile(s) at high velocity. Common firearms include revolvers, self-loading rifles, and shotguns.
3. A cartridge contains the primer, propellant and projectile(s) assembled into a container. It uses the energy from burning propellant gases to launch the projectile(s) down the barrel of the firearm.
Propallent burning
The document discusses different types of propellants used in ballistics and pyrotechnics. It describes various solid and liquid propellant compositions and their uses. Solid propellants can have different grain shapes that determine their burn rate characteristics, such as progressive, digressive, or neutral burns. Common shapes include flake, ball, cord, single perforation, 7-perforation, and 19-perforation grains. Liquid propellants often use combinations of fuels and oxidizers like nitric acid and kerosene or liquid hydrogen and liquid oxygen.
Internal ballistics
This document discusses the topic of internal ballistics, which deals with the motion of projectiles inside a weapon's barrel. It provides information on factors that affect muzzle velocity, such as the quantity and quality of powder, barrel length, and bullet fit. The Le Duc empirical formula is presented, which approximates the velocity-space curve of a projectile in a gun based on distance traveled. The concept of the "all burnt point", where all of the propellant has been consumed, is explained.
Internal ballistic
This document discusses the topic of internal ballistics, which is the science of what occurs inside a firearm when it is discharged. It begins with a brief history of ballistics and defines internal ballistics. Some key phenomena of internal ballistics discussed include ignition, combustion of propellants, barrel length, atmospheric conditions, the shape of cartridge cases, and heat problems during combustion. Lock time and barrel time are also defined. The document provides details on each of these topics as they relate to internal ballistics and ballistic performance.
Terminal ballistics
1. Terminal ballistics deals with the behavior and effects of projectiles when they impact targets and transfer energy. It studies penetration potential and wound ballistics.
2. When a projectile strikes the body, it compresses tissues until they tear beyond their elastic limits if the projectile has enough energy. It continues through an exit wound, causing internal damage.
3. Factors affecting wounding include the target site, velocity, projectile construction, and range. Frontal wounds cause more damage due to shallow tissue depth. Higher velocities increase energy and damage.
Internal ballistics
Internal ballistics is the study of a projectile's behavior from ignition until it exits the gun barrel. It examines factors like lock time, ignition time, and barrel time. Piobert's law states that gunpowder burns layer by layer. Newton's third law means that for every action there is an equal and opposite reaction, causing recoil. Recoil velocity can be calculated using the projectile and gun masses and velocities. Rusting and erosion over time degrade the gun barrel and reduce accuracy.
Firearm and its classification.
The document discusses the classification of firearms. It describes firearms as being classified based on their bore (smooth bore vs rifled), loading mechanism (muzzleloader, breechloader, magazine loader), action (lever, bolt, self-loading), firing capability (single shot vs repeater), how they are handled (handguns vs shoulder arms) and their use (service vs sporting). Primitive firearms discussed include matchlock, wheel-lock, flintlock and muzzleloaders. Modern firearms are classified based on these various characteristics.
External ballistics
The document discusses the factors that affect the trajectory of a bullet, including both internal and external factors. The main internal factors are the velocity of the projectile, spin of the bullet, angle of fire, structural features, and gravity. The main external factors are wind, air resistance, and the Coriolis effect. The trajectory takes the form of a parabola, being affected most significantly by the bullet's velocity, as well as air resistance and gravity acting upon it during flight.
External ballistics
The document discusses external ballistics and the factors that affect the trajectory of a bullet. It defines external ballistics as dealing with the motion of a projectile from the muzzle of a weapon to the target. The main factors that influence a bullet's flight are gravity, which pulls it downward, and air resistance, which reduces its velocity. In a vacuum with no air resistance or gravity, a bullet would travel in a straight line at a constant velocity. However, in reality bullets follow a parabolic trajectory due to these forces. The document also discusses other factors like velocity, spin, angle of fire, yaw, drift, and temperature that can impact a bullet's trajectory.
External ballistics
External ballistics deals with the flight path of a projectile from the moment it exits the barrel until impact with the target. The key factors that influence a projectile's trajectory are wind, vertical angle, and air density. Wind can cause horizontal deflection from crosswinds and vertical deflection from headwinds or tailwinds. The vertical angle of fire affects slant range and requires adjustments to hold-off points. Variations in air pressure, temperature, and humidity that determine air density also influence drag on the projectile and its trajectory.
LIMITING VELOCITY
This document discusses limiting velocity and ballistic limits. It defines external ballistics as dealing with the behavior of a projectile in flight after exiting the gun barrel, and terminal ballistics as studying the effects of a projectile impacting a target. The ballistic limit or limiting velocity is the minimum speed required for a projectile to reliably penetrate a material, below which penetration is unlikely. An equation is presented that relates the ballistic limit velocity to factors like projectile diameter, mass, and material properties.
Terminal ballistics
This document discusses terminal ballistics and the different types of injuries caused by firearms. Terminal ballistics is the study of bullet behavior once it impacts the target. Factors like velocity, mass, size, and shape of the bullet affect the degree of injury. Rifled firearms can cause injuries at contact range (muzzle touching body), close shot (within flame distance), and distant shots over 50cm away. Shotgun wounds depend on range, with contact shots causing discoloration and burns and long range shots rarely being fatal. Entry wounds from firearms show more tissue destruction than exit wounds, which tend to be everted with split flaps. Specific injuries include abrasion collars, contusion collars, tattooing, and blackening
Wound Ballistics Of Rifled Firearm.pptx
This document discusses wound ballistics of rifled firearms. It begins by introducing forensic ballistics and the different types: internal, external, and terminal ballistics. It then discusses wound ballistics, focusing on the mechanism of injury when a projectile strikes a living target. Key factors that influence the transfer of kinetic energy are explored. Different types of gunshot wounds are defined, including penetrating, perforating, and wounds that are both penetrating and perforating. Cavitation effects and characteristics of entry and exit wounds are also summarized.
Chapter15 Firearms
Firearms identification experts can identify key details about firearms from ballistic evidence:
- Rifling marks on bullets can identify the specific gun used due to variations between firearms.
- Firing pin and breechblock markings on cartridge casings are also unique to each gun.
- The type of bullet, firearm, and presence of gunshot residue can provide important clues during investigations.
Improvised Firearms
This document discusses various types of improvised firearms, also known as zip guns. It provides examples such as zip guns, pen guns, pipe guns, and guns disguised as everyday objects like flashlights, cell phones, cigarettes, briefcases, and keychains. It describes how some of these firearms are constructed in a rudimentary way from available materials to function as a weapon. The document cautions that these improvised firearms can be unstable and pose safety risks due to improper materials or assembly.
TERMINAL BALLISTICS.pptx EFFECT OF PROJECTILE ON HIYYING THE TARGET
Terminal ballistics focuses on the behavior of projectiles after impact with a target. It involves studying how projectiles interact with and damage targets, as well as their stopping power. Factors like bullet design, velocity, mass, and shot placement influence a bullet's stopping power and ability to incapacitate. An unstable bullet may have reduced accuracy, an unpredictable trajectory, and wider shot groupings. Bullet instability can arise from issues like improper twist rate, design flaws, extreme velocities, barrel wear, and environmental conditions. Upon impact, an unstable bullet tumbling sideways increases its surface area and thus the size of the entry wound.
Types of injury and range of fire
This document discusses different types of injuries caused by firearms at different ranges. It describes tattooing or stippling caused by unburnt or semi-burnt gunpowder particles deposited in the skin at close range. Blackening is caused by smoke deposits and is limited to a short range. Charring or scorching is burning caused by hot gases from combustion and occurs at very close range, leaving characteristic marks. A pink coloration around a wound indicates absorption of carbon monoxide from combustion, indicating a close-range injury. The document also discusses muzzle patterns left by contact shots and the ranges of different markings like scorching, blackening, and powder residues left by different firearms.
Propellant type and combustion property
The document discusses different types of propellant powders used in firearms. It begins by explaining that black powder, the original propellant, is a mixture of potassium nitrate, charcoal and sulfur that produces smoke and residue when ignited. Smokeless powders were later developed and include single, double and triple base varieties that use nitrocellulose as the primary ingredient. Single base powders use nitrocellulose alone while double and triple base powders add nitroglycerin and nitroguanidine respectively. Semi-smokeless powder contains a mixture of black powder and smokeless powder. Modern substitutes for black powder like Pyrodex were also developed to be safer while retaining similar ballistic properties.
History of firearms
The document provides a history of the development of firearms from early hand cannons to modern systems. It describes the major innovations in ignition mechanisms from matchlock guns to flintlock guns to percussion caps. Important developments included the wheel lock mechanism, snaphaunce, muzzleloaders, Colt's revolver, breechloaders, and the introduction of cartridges using rimfire, pinfire, and centerfire systems. Modern firearms are categorized based on their bore, loading, firing, and handling characteristics.
introduction to forensic ballistics
introductory information related to the field of firearms identification; the evidences, the principles involeved in their examination and the categories of guns.
Disguised writing
What is disguised writing?
To know more about this topic, click on the link- https://youtu.be/qhBBGXGJ5RQ
Chemical tests for GSR
Gunshot residue analysis examines tiny particles of primer and gunpowder that are expelled from guns when fired. These particles can be detected on clothing using chemical tests that identify compounds like barium, antimony, and lead which are components of primer, as well as nitrates from gunpowder. The sodium rhodizonate, Walker, Greiss, Marshall, and Tewari tests are chemical methods used to detect these compounds and determine if gunshot residue is present. If found, the location, shape, and appearance of any gunshot residue patterns on clothing can provide information about a shooting incident.
ammunition and its classification
This document discusses forensic ballistics and ammunition. It begins by defining forensic ballistics as the branch of science dealing with shooting incidents for legal purposes. It then discusses different types of ammunition such as rimfire, centerfire, caseless, and blank ammunition. It describes the components of ammunition including primers, propellants, and bullets. Various bullet types are outlined like full metal jacket, hollow point, ballistic tip, open tip, dum-dum, wire patched, rubber, and incendiary bullets. Improvised ammunition is also briefly discussed.
Ballistics & Toolmark Analysis
The document discusses the history and development of gunpowder, firearms, bullets, and ballistics technology from ancient China to the 19th century. It describes how gunpowder was refined for use in firearms and the development of matchlock, wheel lock, flintlock, and percussion cap firing mechanisms. It also discusses the introduction of rifling in gun barrels and how this improved accuracy. Finally, it summarizes different bullet types, construction methods, and how ballistics analysis can identify class and individual characteristics of firearms and bullets.
Firing Marks
Firing marks left on bullets and cartridge cases can be used to identify the firearm used. There are several types of marks including:
1. Rifling marks on the bullet from the grooves in the barrel. These marks are unique to each gun.
2. Firing pin marks on the primer from the firing pin striking it. Imperfections in the firing pin can be transferred.
3. Breech face marks on the cartridge from the cartridge striking the breech face on firing. Imperfections are imprinted.
4. Extractor and ejector marks on the cartridge case from the mechanisms removing the spent case from the firearm.
Rifled ammunition
This document defines ammunition and its key components. It discusses that ammunition consists of a case, propellant, projectile, and initiation mixture contained in a shell or cartridge. It then describes the main parts of rifle cartridges including the cartridge case, primer, propellant, projectile, and lubricants. The cartridge case houses the other components and comes in different materials like brass. The primer ignites the propellant which propels the projectile through the barrel. Projectiles can be non-jacketed, semi-jacketed, or fully-jacketed bullets made of various materials. Lubricants are also used to reduce friction when fired.
GSR
Gunshot residue is composed of burnt and unburnt particles from the firearm's primer, propellant, bullet, cartridge case, and firearm. There are three types of gunpowder burning - degressive, neutral, and progressive. Gunshot residue can be detected through analytical methods like neutron activation analysis and atomic absorption spectrophotometry, and qualitatively identified with scanning electron microscopy and atomic force microscopy. Gunshot residue is collected using carbon-coated adhesive stubs or alcohol swabs, with stubs having fewer false negatives. Firing distance can be determined using tests like the Greiss test, which can help identify homicide versus suicide or entrance versus exit wounds. Each gunshot residue case must be individually evaluated as test results alone do
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External ballistics
The document discusses the factors that affect the trajectory of a bullet, including both internal and external factors. The main internal factors are the velocity of the projectile, spin of the bullet, angle of fire, structural features, and gravity. The main external factors are wind, air resistance, and the Coriolis effect. The trajectory takes the form of a parabola, being affected most significantly by the bullet's velocity, as well as air resistance and gravity acting upon it during flight.
External ballistics
The document discusses external ballistics and the factors that affect the trajectory of a bullet. It defines external ballistics as dealing with the motion of a projectile from the muzzle of a weapon to the target. The main factors that influence a bullet's flight are gravity, which pulls it downward, and air resistance, which reduces its velocity. In a vacuum with no air resistance or gravity, a bullet would travel in a straight line at a constant velocity. However, in reality bullets follow a parabolic trajectory due to these forces. The document also discusses other factors like velocity, spin, angle of fire, yaw, drift, and temperature that can impact a bullet's trajectory.
External ballistics
External ballistics deals with the flight path of a projectile from the moment it exits the barrel until impact with the target. The key factors that influence a projectile's trajectory are wind, vertical angle, and air density. Wind can cause horizontal deflection from crosswinds and vertical deflection from headwinds or tailwinds. The vertical angle of fire affects slant range and requires adjustments to hold-off points. Variations in air pressure, temperature, and humidity that determine air density also influence drag on the projectile and its trajectory.
LIMITING VELOCITY
This document discusses limiting velocity and ballistic limits. It defines external ballistics as dealing with the behavior of a projectile in flight after exiting the gun barrel, and terminal ballistics as studying the effects of a projectile impacting a target. The ballistic limit or limiting velocity is the minimum speed required for a projectile to reliably penetrate a material, below which penetration is unlikely. An equation is presented that relates the ballistic limit velocity to factors like projectile diameter, mass, and material properties.
Terminal ballistics
This document discusses terminal ballistics and the different types of injuries caused by firearms. Terminal ballistics is the study of bullet behavior once it impacts the target. Factors like velocity, mass, size, and shape of the bullet affect the degree of injury. Rifled firearms can cause injuries at contact range (muzzle touching body), close shot (within flame distance), and distant shots over 50cm away. Shotgun wounds depend on range, with contact shots causing discoloration and burns and long range shots rarely being fatal. Entry wounds from firearms show more tissue destruction than exit wounds, which tend to be everted with split flaps. Specific injuries include abrasion collars, contusion collars, tattooing, and blackening
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This document discusses wound ballistics of rifled firearms. It begins by introducing forensic ballistics and the different types: internal, external, and terminal ballistics. It then discusses wound ballistics, focusing on the mechanism of injury when a projectile strikes a living target. Key factors that influence the transfer of kinetic energy are explored. Different types of gunshot wounds are defined, including penetrating, perforating, and wounds that are both penetrating and perforating. Cavitation effects and characteristics of entry and exit wounds are also summarized.
Chapter15 Firearms
Firearms identification experts can identify key details about firearms from ballistic evidence:
- Rifling marks on bullets can identify the specific gun used due to variations between firearms.
- Firing pin and breechblock markings on cartridge casings are also unique to each gun.
- The type of bullet, firearm, and presence of gunshot residue can provide important clues during investigations.
Improvised Firearms
This document discusses various types of improvised firearms, also known as zip guns. It provides examples such as zip guns, pen guns, pipe guns, and guns disguised as everyday objects like flashlights, cell phones, cigarettes, briefcases, and keychains. It describes how some of these firearms are constructed in a rudimentary way from available materials to function as a weapon. The document cautions that these improvised firearms can be unstable and pose safety risks due to improper materials or assembly.
TERMINAL BALLISTICS.pptx EFFECT OF PROJECTILE ON HIYYING THE TARGET
Terminal ballistics focuses on the behavior of projectiles after impact with a target. It involves studying how projectiles interact with and damage targets, as well as their stopping power. Factors like bullet design, velocity, mass, and shot placement influence a bullet's stopping power and ability to incapacitate. An unstable bullet may have reduced accuracy, an unpredictable trajectory, and wider shot groupings. Bullet instability can arise from issues like improper twist rate, design flaws, extreme velocities, barrel wear, and environmental conditions. Upon impact, an unstable bullet tumbling sideways increases its surface area and thus the size of the entry wound.
Types of injury and range of fire
This document discusses different types of injuries caused by firearms at different ranges. It describes tattooing or stippling caused by unburnt or semi-burnt gunpowder particles deposited in the skin at close range. Blackening is caused by smoke deposits and is limited to a short range. Charring or scorching is burning caused by hot gases from combustion and occurs at very close range, leaving characteristic marks. A pink coloration around a wound indicates absorption of carbon monoxide from combustion, indicating a close-range injury. The document also discusses muzzle patterns left by contact shots and the ranges of different markings like scorching, blackening, and powder residues left by different firearms.
Propellant type and combustion property
The document discusses different types of propellant powders used in firearms. It begins by explaining that black powder, the original propellant, is a mixture of potassium nitrate, charcoal and sulfur that produces smoke and residue when ignited. Smokeless powders were later developed and include single, double and triple base varieties that use nitrocellulose as the primary ingredient. Single base powders use nitrocellulose alone while double and triple base powders add nitroglycerin and nitroguanidine respectively. Semi-smokeless powder contains a mixture of black powder and smokeless powder. Modern substitutes for black powder like Pyrodex were also developed to be safer while retaining similar ballistic properties.
History of firearms
The document provides a history of the development of firearms from early hand cannons to modern systems. It describes the major innovations in ignition mechanisms from matchlock guns to flintlock guns to percussion caps. Important developments included the wheel lock mechanism, snaphaunce, muzzleloaders, Colt's revolver, breechloaders, and the introduction of cartridges using rimfire, pinfire, and centerfire systems. Modern firearms are categorized based on their bore, loading, firing, and handling characteristics.
introduction to forensic ballistics
introductory information related to the field of firearms identification; the evidences, the principles involeved in their examination and the categories of guns.
Disguised writing
What is disguised writing?
To know more about this topic, click on the link- https://youtu.be/qhBBGXGJ5RQ
Chemical tests for GSR
Gunshot residue analysis examines tiny particles of primer and gunpowder that are expelled from guns when fired. These particles can be detected on clothing using chemical tests that identify compounds like barium, antimony, and lead which are components of primer, as well as nitrates from gunpowder. The sodium rhodizonate, Walker, Greiss, Marshall, and Tewari tests are chemical methods used to detect these compounds and determine if gunshot residue is present. If found, the location, shape, and appearance of any gunshot residue patterns on clothing can provide information about a shooting incident.
ammunition and its classification
This document discusses forensic ballistics and ammunition. It begins by defining forensic ballistics as the branch of science dealing with shooting incidents for legal purposes. It then discusses different types of ammunition such as rimfire, centerfire, caseless, and blank ammunition. It describes the components of ammunition including primers, propellants, and bullets. Various bullet types are outlined like full metal jacket, hollow point, ballistic tip, open tip, dum-dum, wire patched, rubber, and incendiary bullets. Improvised ammunition is also briefly discussed.
Ballistics & Toolmark Analysis
The document discusses the history and development of gunpowder, firearms, bullets, and ballistics technology from ancient China to the 19th century. It describes how gunpowder was refined for use in firearms and the development of matchlock, wheel lock, flintlock, and percussion cap firing mechanisms. It also discusses the introduction of rifling in gun barrels and how this improved accuracy. Finally, it summarizes different bullet types, construction methods, and how ballistics analysis can identify class and individual characteristics of firearms and bullets.
Firing Marks
Firing marks left on bullets and cartridge cases can be used to identify the firearm used. There are several types of marks including:
1. Rifling marks on the bullet from the grooves in the barrel. These marks are unique to each gun.
2. Firing pin marks on the primer from the firing pin striking it. Imperfections in the firing pin can be transferred.
3. Breech face marks on the cartridge from the cartridge striking the breech face on firing. Imperfections are imprinted.
4. Extractor and ejector marks on the cartridge case from the mechanisms removing the spent case from the firearm.
Rifled ammunition
This document defines ammunition and its key components. It discusses that ammunition consists of a case, propellant, projectile, and initiation mixture contained in a shell or cartridge. It then describes the main parts of rifle cartridges including the cartridge case, primer, propellant, projectile, and lubricants. The cartridge case houses the other components and comes in different materials like brass. The primer ignites the propellant which propels the projectile through the barrel. Projectiles can be non-jacketed, semi-jacketed, or fully-jacketed bullets made of various materials. Lubricants are also used to reduce friction when fired.
GSR
Gunshot residue is composed of burnt and unburnt particles from the firearm's primer, propellant, bullet, cartridge case, and firearm. There are three types of gunpowder burning - degressive, neutral, and progressive. Gunshot residue can be detected through analytical methods like neutron activation analysis and atomic absorption spectrophotometry, and qualitatively identified with scanning electron microscopy and atomic force microscopy. Gunshot residue is collected using carbon-coated adhesive stubs or alcohol swabs, with stubs having fewer false negatives. Firing distance can be determined using tests like the Greiss test, which can help identify homicide versus suicide or entrance versus exit wounds. Each gunshot residue case must be individually evaluated as test results alone do
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This document discusses the field of anthropology and its branches. It begins by defining anthropology as the study of humans, their origins, and cultural variations throughout history. The document then outlines the major branches of anthropology, including socio-cultural anthropology, physical/biological anthropology, archaeological anthropology, linguistic anthropology, and applied anthropology. For each branch, it provides a brief description of the areas of focus and goals of study.
Study of Soil and Paint
This document provides information about soils and paints. It defines soil as a mixture of organic matter, minerals, gases, liquids, and organisms that support life. The four main components of soil are identified as minerals, water, organic matter, and gases. Key soil types like sand, silt, clay and loam are described. Methods for analyzing soils like determining moisture content and particle size distribution are outlined. The document also defines paint as a liquid that converts to a solid film after application. The main components of paint are identified as pigments, binders, liquids, and additives. Common types of paints like water-based and oil-based are described. Forensic analysis methods for soils and paints are mentioned
Microscope and its types
This document provides information about different types of microscopes. It discusses simple microscopes, which use a single lens for magnification, and their basic parts and working principle. Compound microscopes are then introduced as using multiple lenses to achieve higher magnification than is possible with a simple lens alone. The key parts of a compound microscope are described, including the eyepiece, objective lenses, body tube, arm, and focus adjustments. It explains that light from the illuminator passes through these parts to produce a magnified image for viewing.
History of firearms
The document outlines the 7 phases of development in firearms technology:
1. Cannon lock - An early matchlock design with a pan and touch hole for ignition.
2. Matchlock - Used a slow-burning match cord for ignition which had disadvantages of visibility and damp weather.
3. Wheel lock - The first self-igniting design using a rotating flint mechanism.
4. Snaphaunce - An early flintlock design with a spring-loaded flint arm for ignition.
5. Flintlock - Rapidly replaced earlier designs using flint and steel for reliable ignition.
6. Percussion lock - Introduced in 1820, it used fulminate of
Hair and fiber
Hairs and fibers are important forms of trace evidence that can provide clues in forensic investigations. Hair has a cuticle, cortex, and sometimes a medulla, and characteristics like these can be used to identify a sample's origin. Fiber analysis examines properties such as the fiber's structure, color, and chemical composition to determine its type (natural or synthetic) and match it to a potential source. Due to their tendency to shed easily, fibers are commonly found as trace evidence and can link a suspect to a crime scene or victim.
Hair and fiber
This document discusses hair and fibers in forensic science. It provides details on:
- The structure and composition of hair, including the cuticle, cortex, and medulla layers. Hair characteristics like color, length and shape can indicate where on the body it came from. Nuclear and mitochondrial DNA can be extracted from hair roots or cuticles.
- Fibers are long thin strands that can be spun into yarn and woven into fabrics. Matching unique fibers between a victim and suspect's clothing can provide evidence of contact.
- Both natural fibers like cotton and wool and synthetic fibers like nylon and polyester are important in forensic analysis and can be identified under a microscope.
Expert Witness Testimony
The document discusses the role and types of expert witnesses. An expert witness is a person with specialized knowledge or experience in a particular field who provides expert testimony. They may provide opinions on matters like injury severity, sanity, machine failures, damages, and authenticating electronic evidence. Expert testimony is important in many civil and criminal cases. Experts have a responsibility to provide unbiased opinions. There are testifying experts who present in court and non-testifying experts who advise lawyers. In ballistics cases, expert opinions on matching bullets to guns involve subjective assessments.
Microscopy
The document discusses different types of microscopes, including compound microscopes and stereomicroscopes. It describes the key parts and principles of operation. Compound microscopes use multiple lenses to magnify specimens and provide a two-dimensional image. Stereomicroscopes use two optical paths to provide a three-dimensional view of surface details. Examples of uses include biology studies, forensics, manufacturing quality control, and more. The document also discusses who may have invented the compound microscope and provides references for further reading.
Chromatography
Chromatography is a technique used to separate mixtures and involves dissolving the mixture in a mobile phase that carries it through a structure containing a stationary phase. It was first developed in 1900 by Russian scientist Mikhail Tsvet and involves the interaction between a mobile and stationary phase resulting in separation. Common types include paper chromatography, thin layer chromatography, gas chromatography, and affinity chromatography. It has various applications in fields like clinical analysis, protein purification, forensic toxicology, and separation of amino acids, proteins, carbohydrates, and more.
Glass fractures
The document discusses different types of glass and forensic analysis of glass evidence. It provides information on the physical, optical, and chemical properties of glass that can be analyzed forensically. Specific techniques mentioned include refractive index testing, density determination, microscopic analysis of fractures, and elemental analysis. The document also discusses how analysis of glass evidence can help reconstruct crime scenes and connect suspects to crimes by matching glass fragments.
RICOCHET
Ricochet refers to a bullet deflecting off a hard surface rather than penetrating it. Many factors influence ricochet behavior, including bullet shape, material, velocity, spin, target material, and angle of incidence. High velocity rifle bullets have a greater chance of penetrating rather than ricocheting. Elongated rifle bullets have higher sectional density than handgun bullets, influencing penetration. Harder target materials like bone are more likely to cause ricochet. The angle of ricochet is difficult to predict due to bullet deformation. Ricochets can cause unintended damage and be lethal if the bullet or fragments strike a person. Wounds from ricocheting bullets will have ragged, irregular edges. Ricoche
Bullets
The document discusses different bullet shapes and designs. It describes that bullets must form a tight seal with the gun's bore while also engaging the rifling without damage. This allows for high accuracy. Several bullet shapes are then outlined, including spitzer bullets which are aerodynamic for accuracy at long ranges. Boat tail bullets provide accuracy, and hollow point boat tail bullets are primarily used for hunting big game at long distances. Different bullet materials and designs trade off velocity, accuracy and intended uses.
More from Ketan Patil (20)
Recently uploaded
Holsinger, Bruce W. - Music, body and desire in medieval culture [2001].pdf
Music and Medieval History
Alternate Wetting and Drying - Climate Smart Agriculture
Alternate Wetting and Drying - Climate Smart AgricultureInternational Food Policy Research Institute- South Asia Office
PPT on Alternate Wetting and Drying presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024. Farming systems analysis: what have we learnt?.pptx
Presentation given at the official farewell of Prof Ken Gillet at Wageningen on 13 June 2024
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
fermented food science of sauerkraut.pptx
This ppt contains the production of a fermented food name - sauerkraut
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...ABHISHEK SONI NIMT INSTITUTE OF MEDICAL AND PARAMEDCIAL SCIENCES , GOVT PG COLLEGE NOIDA
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...
We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
−
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
�
(
�
−
�
)
∼
0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNe Ia. While these characteristics are consistent with some Ca-rich SNe Ia, particularly SN 2016hnk, SN 2023adsy is intrinsically brighter than the low-
�
Ca-rich population. Although such an object is too red for any low-
�
cosmological sample, we apply a fiducial standardization approach to SN 2023adsy and find that the SN 2023adsy luminosity distance measurement is in excellent agreement (
≲
1
�
) with
Λ
CDM. Therefore unlike low-
�
Ca-rich SNe Ia, SN 2023adsy is standardizable and gives no indication that SN Ia standardized luminosities change significantly with redshift. A larger sample of distant SNe Ia is required to determine if SN Ia population characteristics at high-
�
truly diverge from their low-
�
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
Methods of grain storage Structures in India.pdf
•Post-harvestlossesaccountforabout10%oftotalfoodgrainsduetounscientificstorage,insects,rodents,micro-organismsetc.,
•Totalfoodgrainproductioninindiais311milliontonnesandstorageis145mt.InIndia,annualstoragelosseshavebeenestimated14mtworthofRs.7,000croreinwhichinsectsaloneaccountfornearlyRs.1,300crores.
•InIndiaoutofthetotalproduction,about30%ismarketablesurplus
•Remaining70%isretainedandstoredbyfarmersforconsumption,seed,feed.Hence,growerneedstoragefacilitytoholdaportionofproducetosellwhenthemarketingpriceisfavourable
•TradersandCo-operativesatmarketcentresneedstoragestructurestoholdgrainswhenthetransportfacilityisinadequate
Gadgets for management of stored product pests_Dr.UPR.pdf
Insectsplayamajorroleinthedeteriorationoffoodgrainscausingbothquantitativeandqualitativelosses
Wellprovedthatnogranariescanbefilledwithgrainswithoutinsectsastheharvestedproducecontainegg(or)larvae(or)pupae(or)adultinsectinthembecauseoffieldcarryoverinfestationwhichcannotbeavoidedindevelopingcountrieslikeIndia
Simpletechnologiesfortimelydetectionofinsectsinthestoredproduceandtherebyplantimelycontrolmeasures
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3:国家专业人才认证中心颁发入库证书
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(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...Scintica Instrumentation
Targeting Hsp90 and its pathogen Orthologs with Tethered Inhibitors as a Diagnostic and Therapeutic Strategy for cancer and infectious diseases with Dr. Timothy Haystead.Direct Seeded Rice - Climate Smart Agriculture
Direct Seeded Rice - Climate Smart AgricultureInternational Food Policy Research Institute- South Asia Office
PPT on Direct Seeded Rice presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
Anti-Universe And Emergent Gravity and the Dark Universe
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Recently uploaded (20)
Holsinger, Bruce W. - Music, body and desire in medieval culture [2001].pdf
Holsinger, Bruce W. - Music, body and desire in medieval culture [2001].pdf
Alternate Wetting and Drying - Climate Smart Agriculture
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Farming systems analysis: what have we learnt?.pptx
Farming systems analysis: what have we learnt?.pptx
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...
MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MIC...
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
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Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...
Gadgets for management of stored product pests_Dr.UPR.pdf
Gadgets for management of stored product pests_Dr.UPR.pdf
Microbiology of Central Nervous System INFECTIONS.pdf
Microbiology of Central Nervous System INFECTIONS.pdf
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Juaristi, Jon. - El canon espanol. El legado de la cultura española a la civi...
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Anti-Universe And Emergent Gravity and the Dark Universe
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Internal Ballistics
- 1. BURNING OF PROPELLANT (INTERNAL BALLISTICS)
- 2. Internal ballistics is the study of what happens within the barrel of a weapon from the moment the firing pin hits the primer to the time the bullets exits from the barrel. It is mainly concerned with propellant pressures, acceleration of the missile whilst it is in the bore, muzzle velocity and recoil.
- 3. When a projectile weapon is launched from the gun barrel, it is accelerated to a high velocity by the burning of propellant.The propellant may travel with the projectile or be stationary in the barrel.The gasses produced by the burning propellant are trapped in the volume behind the projectile.The introduction of more heat into the product gasses causes the pressure to rise which in turn will accelerate the projectile. On the other hand, the movement of the projectile increases the volume which tends to drop the pressure.
- 5. There are three different types of powder which helps in propellant burning which are as follows PROGRESSIVE POWDER as burning proceeds, the total burning surface increases. Multi-perforated and rosette grains burn progressively
- 6. Fig :showing multiple perforated grain fig.showing Progressive powder curve
- 7. DEGRESSIVE POWDER as As burning proceeds, the total burning surface decreasestotal Propellants formed in pellets, balls, sheets, strips, or cord burn degressively. Fig showing curve for degressive powder
- 8. CONSTANT BURNING POWDER OR NEUTRAL BURNING as burning proceeds the total burning surface remains approximately constant Single perforated grains and star perforations result in neutral burning Fig. showing single perforated grain
- 9. Fig. showing curve for neutral or constant burning
- 10. COMBUSTION:- Oxidation reduction process. It takes place when the reaction of the burning propellant/substance arise out of its contact with the air in an open space. Oxidation- o2 molecule is added Reduction-02 molecule is reduced
- 11. DEFLAGRATION:- it includes violent and rapid burning and is intermediary step between gradual combustion and detonation Slow rate of burning E.g. in low explosives such as propellant DETONATION:- It takes place when the explosion is extremely rapid and the formation of gases is almost instantaneous E.g. in high explosives