How a Firearm Works

The same physical process is used to fire shotshells from shotguns or cartridges from rifles or handguns. Pulling the trigger causes the firing pin to strike and explode the primer in the base of the cartridge or shotshell. The spark from the primer ignites the gunpowder, which burns rapidly and converts to a gas. The gas rapidly expands and drives the projectile(s) through the barrel with great force.

How the rifle and handgun fire:

1. A cartridge is inserted into the chamber.
2. The action is closed, and the firing pin is pushed back and held back under spring tension.
3. The trigger is squeezed, releasing the firing pin, which moves forward with great force. The firing pin strikes the primer, causing it to explode.
4. The spark from the primer ignites the gunpowder. Gas converted from the burning powder rapidly expands in the cartridge.
5. The expanding gas forces the bullet out of the cartridge and down the barrel with great speed.
6. The rifling in the barrel (see Differences Between Rifles, Shotguns and Handguns) causes the bullet to spin as it travels out of the barrel. The bullet's speed and escaping gases produce a "bang."

How the shotgun fires:

1. A shotshell is inserted into the chamber.
2. The action is closed, and the firing pin is pushed back and held back under spring tension.
3. The trigger is pulled, causing the firing pin to strike the primer producing a spark.
4. The spark from the primer ignites the gunpowder. Gas converted from the burning powder expands in the shell.
5. The gas pushes the wad against the shot; the wad and shot are forced out of the plastic body of the shell.
6. The wad and shot leave the barrel. The escaping gases produce a "bang."
7. The shot and wad separate. The shot cluster spreads and forms a pattern.