CFA Action Type & Caliber Classification 3 — Questions and Answers
Question 1: When appraising a firearm marked '9mm Luger,' a CFA should recognize this cartridge as interchangeable with:
- .380 ACP
- 9mm Parabellum (Correct answer)
- 9mm Makarov
- .38 Special
Correct answer: 9mm Parabellum
9mm Luger and 9mm Parabellum (also written 9x19mm) are the same cartridge, developed by Georg Luger in 1901.
Question 2: A lever-action rifle's action type is primarily distinguished by:
- A rotating bolt operated by a side-mounted lever
- A loop lever behind the trigger guard that cycles the action (Correct answer)
- A gas-operated piston that unlocks the bolt
- A thumb-operated hammer that advances the cylinder
Correct answer: A loop lever behind the trigger guard that cycles the action
Lever-action rifles use a loop lever located behind the trigger guard; pushing it down and forward then returning it cycles the action.
Question 3: In the context of firearm classification, 'caliber' expressed in millimeters refers to:
- The weight of the bullet in grams
- The diameter of the bore measured across the lands (Correct answer)
- The overall cartridge length
- The muzzle energy in joules
Correct answer: The diameter of the bore measured across the lands
When expressed in millimeters, caliber refers to the bore diameter measured across the lands (the high points of the rifling).
Question 4: A gas-operated semi-automatic rifle diverts propellant gas to cycle the action. Which component does the gas typically act upon first?
- The firing pin
- The extractor claw
- A piston or gas key on the bolt carrier (Correct answer)
- The magazine follower
Correct answer: A piston or gas key on the bolt carrier
In gas-operated actions, expanding gas is tapped from the barrel and acts upon a piston or, in direct-impingement systems, a gas key on the bolt carrier to unlock and cycle the action.
Question 5: Which of the following cartridges is classified as a magnum rifle caliber?
- .30-30 Winchester
- .308 Winchester
- .300 Winchester Magnum (Correct answer)
- .30-06 Springfield
Correct answer: .300 Winchester Magnum
.300 Winchester Magnum is a belted magnum cartridge offering significantly higher velocity and energy than standard .30 caliber rounds like the .308 or .30-06.
Question 6: A CFA encounters a shotgun labeled '20 gauge.' Compared to a 12-gauge shotgun, the 20-gauge barrel has a:
- Larger bore diameter
- Smaller bore diameter (Correct answer)
- Identical bore diameter with different chamber length
- Larger bore diameter but shorter barrel
Correct answer: Smaller bore diameter
20-gauge shotguns have a smaller bore diameter than 12-gauge; higher gauge numbers indicate smaller bore sizes in shotgun classification.
Question 7: An 'open-bolt' firearm fires from the open-bolt position, meaning:
- The safety is always engaged when the bolt is forward
- The bolt is held rearward by the sear and travels forward to chamber and fire simultaneously (Correct answer)
- The chamber is exposed for inspection when the safety is off
- The bolt locks open automatically after every shot
Correct answer: The bolt is held rearward by the sear and travels forward to chamber and fire simultaneously
Open-bolt firearms hold the bolt rearward when cocked; pulling the trigger releases it to travel forward, chambering and firing the round in one motion.
CFA Action Type & Caliber Classification 3
When appraising a firearm marked '9mm Luger,' a CFA should recognize this cartridge as interchangeable with: