Firearm Types and Mechanisms Flashcards

What distinguishes a semi-automatic pistol from a revolver?

Answer: A semi-automatic uses a detachable magazine and cycles the action automatically

Semi-automatic pistols feed from a detachable magazine and use energy from firing to chamber the next round automatically.

What is the function of a firearm's extractor?

Answer: It removes the spent case from the chamber after firing

The extractor grips the cartridge rim and pulls the spent case out of the chamber after the round is fired.

In a double-action revolver, what happens when the trigger is pulled?

Answer: The hammer cocks and then falls in a single trigger pull

A double-action revolver both cocks the hammer and releases it with a single continuous trigger pull.

What does 'gauge' measure when describing a shotgun?

Answer: The bore diameter expressed as the number of lead balls of that diameter making one pound

Shotgun gauge is historically defined as the number of pure lead balls of the bore diameter that together weigh one pound.

What type of action ejects a spent shell and chambers a new one by manually sliding the forestock backward and forward?

Answer: Pump action

A pump-action (slide-action) firearm cycles by moving the forestock rearward then forward, ejecting the spent case and chambering a fresh round.

Which component of a semi-automatic pistol holds rounds and feeds them into the chamber?

Answer: The detachable magazine

The detachable magazine stores cartridges under spring tension and feeds them one at a time into the chamber.

What is the purpose of rifling inside a firearm barrel?

Answer: To impart spin on the bullet, stabilizing it in flight

Rifling consists of helical grooves cut into the barrel that spin the bullet, gyroscopically stabilizing it for improved accuracy and range.