NRA Firearm Repair & Restoration Techniques 2

Question 1

When re-crowning a rifle barrel, which tool is most appropriate for producing a target-grade recessed crown?

Accepted Answer

11-degree carbide cutter with a pilot

Answer

An 11-degree carbide cutter with a pilot centers itself in the bore and cuts a consistent, precise recessed crown that protects the rifling and improves accuracy.

Question 2

A revolver exhibits cylinder timing issues where the cylinder does not lock up fully before the hammer falls. Which component is the MOST likely cause?

Accepted Answer

Cylinder hand (pawl)

Answer

The cylinder hand (pawl) advances and indexes the cylinder; wear on its tip or engagement surface causes the cylinder to under-rotate and fail to lock up in time.

Question 3

What is the correct procedure when using a barrel vise and action wrench to remove a stubborn barrel from a rifle action?

Accepted Answer

Clamp the barrel firmly in the vise and rotate the action wrench counter-clockwise when viewed from the muzzle

Answer

Standard barrel threads are right-hand, so the action (receiver) must be turned counter-clockwise (when viewed from the muzzle) to unscrew it from the barrel.

Question 4

During stock refinishing, a gunsmith discovers checking that has been partially filled with old finish. The best method to restore crisp, sharp checking is to:

Accepted Answer

Use a single-cut checkering file to deepen and clean out the grooves, then re-run border lines

Answer

A single-cut checkering file is run through each groove to remove old finish and re-define the diamonds before re-cutting the borders.

Question 5

A semi-automatic pistol consistently fails to feed the last round from a magazine. The most logical first diagnostic step is to:

Accepted Answer

Inspect and measure the magazine follower angle and spring tension

Answer

Last-round feed failures most often result from a weak or canted magazine follower that does not present the final cartridge at the correct angle for the slide to chamber it.

(NRA) National Rifle Association Certified Gunsmith Practice Test

(NRA) National Rifle Association Certified Gunsmith Practice Test

NRA Firearm Repair & Restoration Techniques 2