(Discussion and Begin Worksheet - Firearms) Tuesday February 28, 2017 (Discussion and Begin Worksheet - Firearms)

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Summative or Formative # Assignment Summative or Formative # Date Issued Gone Missing Day Last Day Accepted QUIZ 12 S3 2/26 Friday

Firearms: A Quick History Almost every gun is based on the same simple concept: You apply explosive pressure behind a projectile to launch it down a barrel. The earliest & simplest application of this idea is the cannon.

The first hand-held guns were essentially mini-cannons; you loaded some gunpowder & a steel ball & lit a fuse.

War typically resulted in the need for improved weapons technology. In the late 1800’s, the revolver quickly became popular due to it’s size & quick loading. It only had to be reloaded every 5-6 shots instead of after each shot.

Handguns have reigned supreme for the past 200 years, and to this day remain the most popular and readily available firearm.

Firearms Identification Often confused with the term ballistics Ballistics is the study of a projectile in motion. Inside the firearm After it leaves the firearm When it impacts the target

Firearms Identification Identification of firearms is based upon this basic idea: A harder object marks a softer one & imparts/transfers its microscopic irregularities to that object.

Questions Facing the Forensic Firearms Expert Did a suspect use this gun to kill that person? Did these bullets come from that gun? Was it really self-defense? Is this a case of suicide, or is foul play involved?

Forensic Firearms Expert Bullet Comparison Weapons Function Is it safe? Has it been modified? Serial Number Restoration Gunpowder Residue Detection on clothes, hands, & wounds Muzzle-to-Target Distances

Pulling the Trigger Pulling the trigger releases the firing pin… The firing pin strikes the primer… The primer ignites the gun powder… The powder generates gas that propels the bullet forward through the barrel & ejects the spent cartridge case.

Caliber: the diameter of the gun barrel Caliber: the diameter of the gun barrel. In guns, particularly firearms, caliber is the approximate internal diameter of the barrel, or the diameter of the projectile it fires.  Caliber is recorded in hundredths of an inch (.22, .38, .44, etc.) millimeters (7mm, 9mm, etc)

World’s Most Powerful Handgun? Smith and Wesson 500 with its “little” brother the 44 magnum.

Begin Worksheet Firearms