Most modern firearms are rifled with the exception of the shotgun. The process of rifling the barrel creates unique patterns. These patterns are called tool mark impressions. The forensic technique of analyzing the impressions left on the bullet is call ballistic fingerprinting. There are two types of strations, class characteristics and individual characteristics. Class characteristics are shared by on type of gun and manufacture, for example a colt peacemaker has 6 lands and grooves left-hand twist. The individual characteristics are specific to the individual gun, for example any imperfections of the lands and grooves caused by the tool 's use in the rifling process or normal wear of the bore.
There are many types of barrels and barrel …show more content…
The shape of the rifling also contributes to the difficulty. “Polygonal rifling takes on a shape that is sometimes referred to as "hills and valleys." This gradual transition prevents firearm examiners from measuring the individual rifling elements in a polygonal rifled barrel.”(Doyle) The standard process for comparing bullet is my measuring the land and groove widths. But this process cannot be achieved with the polygonal barrels. The reason is because there is no defined beginning and end to the hills and valleys in the …show more content…
The problem with this is the individual characteristics change over time from wear and cleaning. Another reason is as a weapon is used copper is striped of the jack of the bullet and will change the striations on the bullet. “NRA representatives say that bullets and shell casings can be altered easily and such tampering can make the ballistic fingerprints useless. The NRA adds that guns used in crimes are often stolen so tracing a gun to its original buyer can prove fruitless.”(Fleischer) But one British researcher proposed that bullets be coated in pollen, “Pollen grains are sticky enough and have a sufficiently hard outer case to survive being fired. They also attach themselves to the clothing and hands of people who handle the ammunition and the gun, providing an additional forensics clue”(Wolf). This would allow a bullet manufacture to be identified quickly, possible a distributor and store. This would greatly help narrow the suspect pool. But many ammo manufactures probably would not to get involved in investigations. In conclusion the process for ballistic fingerprinting can be helpful for investigators under the right circumstances. But only a very small portion of guns could not be identified though using this forensic method. Cataloging ballistic fingerprints of every gun before it leaves the manufacture would not be effective. Because if a criminal
There are many types of barrels and barrel …show more content…
The shape of the rifling also contributes to the difficulty. “Polygonal rifling takes on a shape that is sometimes referred to as "hills and valleys." This gradual transition prevents firearm examiners from measuring the individual rifling elements in a polygonal rifled barrel.”(Doyle) The standard process for comparing bullet is my measuring the land and groove widths. But this process cannot be achieved with the polygonal barrels. The reason is because there is no defined beginning and end to the hills and valleys in the …show more content…
The problem with this is the individual characteristics change over time from wear and cleaning. Another reason is as a weapon is used copper is striped of the jack of the bullet and will change the striations on the bullet. “NRA representatives say that bullets and shell casings can be altered easily and such tampering can make the ballistic fingerprints useless. The NRA adds that guns used in crimes are often stolen so tracing a gun to its original buyer can prove fruitless.”(Fleischer) But one British researcher proposed that bullets be coated in pollen, “Pollen grains are sticky enough and have a sufficiently hard outer case to survive being fired. They also attach themselves to the clothing and hands of people who handle the ammunition and the gun, providing an additional forensics clue”(Wolf). This would allow a bullet manufacture to be identified quickly, possible a distributor and store. This would greatly help narrow the suspect pool. But many ammo manufactures probably would not to get involved in investigations. In conclusion the process for ballistic fingerprinting can be helpful for investigators under the right circumstances. But only a very small portion of guns could not be identified though using this forensic method. Cataloging ballistic fingerprints of every gun before it leaves the manufacture would not be effective. Because if a criminal