This introduction to forensics worksheet is designed to help you paraphrase or put reading into your own words so that when you review it later, you will understand it better and it will be easier to remember the information too! Write like you are explaining this to a 10 year old.

You are to read all 8 paragraphs and then write in your own words
Name _______________________________
Reading and Paraphrasing Activity 1:

Ballistic Signatures and how they can be used to solve a crime:

1.When lands and grooves grab and spin a projectile, or bullet, moving down the barrel of a firearm, they also create cuts in the projectile. These cuts leave behind distinctive markings that are at the heart of firearms comparisons. Lands, or ridges, refer to the high parts made when the factory makes cuts into the barrel of a firearm to make grooves, the low parts. These lands and grooves create markings known as striations on the projectile. Striations are straight and parallel to the longitudinal axis of the projectile. One can see that striations are more prevalent on soft lead bullets than they are on metal or jacketed bullets.

1.My summary of the above paragraph:



2.Silencers are gadgets that are designed to suppress or muffle the report of a gunshot. These can include a shirt wrapped around the barrel to a high-tech sound-absorbing screw-on attachment. Such attachments can also leave behind distinctive markings on projectiles, but these markings are not predictable. If a silencer does leave distinctive impressions on the projectile but is not available for examination by the time the forensic firearms examiner test-fires the gun, these impressions may hinder the scientist’s attempt to find a match between the bullet and the gun from which it was fired.

2. My summary of the above paragraph:
Silencers are something you put on gun so you can hide the sound of you firing it. Some people use a shirt around the barrel and some people attach a high tech screw on attachment.







3. In addition to the presence of lands, grooves, striations, and twists, each rifled barrel has minute qualities that set it apart from all others. A rifled gun barrel is the result when the manufacturer carves spiral grooves into the parietal surface of the barrel in order to make projectiles spin as they are forced down the barrel. This spinning action allows the bullet to stabilize itself during flight. This is the same physics concept with footballs as the quarterback passes the spinning ball to the receiver waiting to catch the ball down the field. For this reason, gun barrels are said to be rifled in order to promote the spinning of a bullet.

3. My summary of the above paragraph:

4. For the purposes of forensics, a rifling tool cuts through each metal gun barrel a bit differently. As subsequent barrels are carved out, the cutting or carving equipment becomes worn with repeated use. This progressive wear and tear creates rifling patterns that differ from one barrel to another. Furthermore, repeated firing also wears down and damages the lands and grooves. This action makes each barrel unique as well as each bullet that passes through it.

4. My summary of the above paragraph:
5. In a nutshell, projectiles fired from the same firearm have the same striated patterns, but bullets fired from different ones do not. The microscopic striations found on a projectile are so unique that they are indicative that the bullet had to come from a particular gun excluding all others. This singles out one gun that sets it apart from others of the same make and model.

5. My summary of the above paragraph: