Bullet Comparison And Analysis : Firearms And Tool Marks Division Of Most Forensic Science Laboratories

An investigation involving a firearm is a specialty of forensic science which focuses on the examination of firearms linked to ballistics. Ballistics is related to finding out the exact flight path of projectiles. Ballistics is the area of study that examines the exact path of the bullet from the moment it leaves the muzzle of the firearm up until it hits the target. During examination many items are collected for evidence including the firearm, bullets, live ammunition, cartridge casings, trace materials such as powder residue, and anything damaged by the projectile. Firearms are often divided into three processes: Internal, External, and Terminal Ballistics. Internal refers to the inside of the firearm; the space of time in which the shooter pulls the trigger, and the when the bullet is exiting. External ballistics is the flight between leaving the muzzle of the firearm, and it striking its target. Terminal ballistics is the impact of ballistics that refers to the examination in which the projectile strikes a target. All firearms leave markings on the cartridge casings once expelled when firing. Ballistic identification and microstamping laws make it possible to link a cartridge recovered to the

Forensic ballistics and firearm investigation begin when the bullets, cartridges, a weapon, or any combination of the above found at a crime scene. With the evidence, a crime laboratory will explore for clues on some things that might cause a suspect or possible to prove that the things were used in the crime. By contrast, the markings on the bullets or cartridges found at the scene with those discharged from the suspect’s weapon, a ballistics expert will typically confirm if the rounds came from a similar weapon. Just the act of cycling a cartridge through the weapon without firing it will leave permanent scratches on the case that is distinctive to the weapon.

If it doubt, do not dust for prints, submit in person to the laboratory and request that the firearm be processed for prints. After processing the scene, the evidence should be sent to the laboratory, personal delivery is preferred. A loaded handgun may be transported in a specially constructed box which has a means of securely holding the firearm and has a metal plate blocking the muzzle. If the firearm is to be sent by mail it must be unloaded and securely packaged. At the end, make a sketch of the area which shows the location of each evidence item collected. The sketch should contain location measurements which reference each evidence item to a fixed object or a reference point. Photographs should be used to supplement notes and sketches, but not as a substitute for them. For later identification the serial number of a firearm should be recorded. Some older rifles and shotguns, may not have a serial number. If the firearm is marked for identification by scribing, the marks should be placed in a location where they will not damage the appearance or value of the

Why do you think it is so important that all evidence be identified (such as marking the bullets and tagging firearms)? What consequences might result if these procedures were not followed?

However, according to a documented FBI ballistics test carried out on October 12, 1975, the AR-15 rifle found in Robideau's car didn't match bullet found on the scene; even if it is assumed to be Peltier's gun, the gun cannot be linked to any bullets found in the crime scene (Incident). The FBI also did another, less effective form of test on the bullet that showed that the bullet might have come from the damaged gun. (Incident) However, since the second method of testing was more prone to fault, error, and interpretation of the agents, it should not be used in light of the first. The best the FBI could prove from the test was that the bullet came from

It is important for a forensic scientist to determine the distance from a gun to a shooter because in some cases a

We also took his clothing and shoes into evidence for testing. During the testing of the clothes we were looking for Primer Residue, which are the particles that come from the gunpowder explosion when the weapon is fired.

A 9mm luger round was discovered immediately after the alert of the victim. Then two 45 GPL CP round were discovered approximately 1 inch apart from each other at 0711. Close-up and medium range pictures were then taken of the bullets. A 9mm Luger was discovered with a red stain on the bullet at 0713 approximately 1.9 feet away from the tree on the scene. A sample was then collected and sent to the lab for testing at 0716. Talking to the officers at the hospital it was found that victim never woke-up and no other evidence was discovered on the scene. A cylindrical piece of metal was found at 0719 and documented and

The miscellaneous ammunition was placed in a box, sealed and weighed. The box of ammunition weighed 10.8 pounds. A property receipt was completed. The box of ammunition and the original copy of the property receipt was placed in a Property Evidence locker located in District II. I forwarded copies of the property receipt to Records and CID.

Do you know what the steps are when it comes to processing firearms evidence? The first step to processing a firearm as evidence is to put gloves on your hands. Then you should take pictures of the gun when you find it at the crime scene. Make sure the picture is as clear as possible because it will be used in the court room. Make sure you included some form of measuring the gun that is in the picture. Next, take the bullets out of the gun and put the bullets in a line. Take a picture of it so the court can see the amount of bullets that was found at the crime scene in each gun. You also need to take pictures of all of the empty bullet shells that you may

Perfect example would be the 7.62x51mm vs. .308, both cartridges use a .304-.307 projectile. The .308 however, has a moderate charge and has less bore pressure associated with it. Unlike the 7.62x51mm which tend to run on the higher end of the spectrum, in terms of bore pressure. It’s important to identify whether your rifle is designated to .308 vs. 7.62x51mm. It can directly affect the longevity of the barrel, and if not checked it can be a detriment to the overall safety of the shooter. Having the ability to identify specific cartridges is a skillset that is dire. I’m going to cover the importance of being able to identify

As is with both the previous two types when collecting evidence for a shoulder firearm or a long gun, the forensic technician is to assign an evidence number, photograph orientation and close-up views of the long gun in place, and take measurements of the firearm’s location prior to collection. The forensic technician should hold the firearm by the grip or stock and avoid contact with any smooth surfaces that may yield latent fingerprints. As with any firearm, this should also be pointed downward and away from people. It is very important that nothing is put inside the barrel of the gun as it can scratch the barrel or contaminate trace evidence or DNA that may be inside the barrel. (Tina Young,

Along with everything else in Forensics, you want to make sure you wear the proper gloves and facemask to avoid contamination of evidence. Make sure the weapon is unloaded before you submit into the lab. In the case of a revolver you want to make sure to note stating which chamber was in the firing position.

Gunshot residue (GSR) is regarded as one of the key evidences when it comes to any kind of shooting case. It helps in determining numerous factors about the crime scene and accurate assessment of gunshot wounds. Unfortunately, it is not certain that the body found on the scene will display the characteristics of crime scene. Instead, most of the time victims are found partially/fully decomposed, submerged in water for longer period, buried or even skeletonized. The macroscopic gunshot wounds are recognizable in the early stages of death but most of the time the gunshot lesions are not distinguishable from other kind of injuries such as laceration or a stab wound due to insect activity. There is not much research conducted on the presence of

Most of the crimes that are committed in our society involve a handgun. Gunshot wounds can be very challenging on determining whether or not it was a suicide attempt or homicide. There are some indicators that assist investigators reach a conclusion on gunshot wounds. One of the indicators is the location of the gunshot wound such as the entry and exit points. For example, as the bullet passes through the skin inward and can often travel through the body on a straight path. Furthermore, the damage to the tissue around a gunshot wound helps the investigators with the determining the distance the weapon was fired from (Swanson, Chamelin, Territo, & Taylor, 2012).