NRA Firearm Inspection & Testing Procedures Flashcards

What does 'timing' refer to in revolver inspection, and what happens when timing is off?

Answer: The synchronization of cylinder rotation so each chamber is fully indexed with the barrel before the hammer falls — poor timing causes bullets to shave lead or miss the bore entirely

Revolver timing ensures the cylinder is fully locked in alignment with the barrel at the moment of firing — out-of-time revolvers can shave lead, damage the forcing cone, and create dangerous conditions.

What is the purpose of using 'snap caps' during a function check or dry-fire testing?

Answer: To protect the firing pin and chamber from damage during dry-fire practice and to test feeding, extraction, and ejection reliably

Snap caps simulate cartridges during dry-fire and function checks, protecting firing pins (especially in rimfire guns) and allowing extraction/ejection testing.

When inspecting a firearm's stock for cracks, which area is most critical to check on a bolt-action rifle?

Answer: The wrist (grip area) behind the action, which bears the most stress and is most prone to cracking

The wrist of the stock experiences the highest recoil stress concentration and is the most common failure point on wooden stocks, especially after heavy use.

What should a gunsmith do before returning a firearm to a customer after service?

Answer: Document the work performed, conduct a final function check, and confirm the firearm operates safely and as intended

Documenting work and performing a final function check protects both the customer and the gunsmith by confirming the firearm was returned in safe, working order.

What is 'chamber casting' (using Cerrosafe) used to diagnose?

Answer: The exact chamber dimensions, allowing identification of the cartridge it is chambered for and any headspace or dimensional issues

A Cerrosafe cast produces a precise replica of the chamber that can be measured to determine the caliber, headspace, and whether the chamber is within specifications.

What does inspecting the extractor of a semi-automatic firearm involve, and what common failure is looked for?

Answer: Checking extractor tension, hook depth, and condition — common failures include weak tension causing extraction failures or a chipped hook causing case slippage

The extractor must maintain proper spring tension and have an undamaged hook; worn or weak extractors are a leading cause of failure-to-extract malfunctions.