NRA NRA Tools & Equipment for Gunsmithing 1 — Questions and Answers
Question 1: What is a 'headspace gauge set' and why is it essential in gunsmithing?
- A set of bore brushes for cleaning different calibers
- Go, No-Go, and Field gauges used to verify that chamber headspace is within safe specifications (Correct answer)
- Gauges that measure barrel wall thickness
- Instruments used to check trigger pull weight
Correct answer: Go, No-Go, and Field gauges used to verify that chamber headspace is within safe specifications
Headspace gauges (Go, No-Go, Field) verify the critical chamber dimension to ensure safe and reliable cartridge feeding and firing.
Question 2: What is the purpose of a 'barrel vise' in gunsmithing?
- To hold the barrel while painting
- To securely hold the barrel during barrel removal, installation, or threading operations without damaging the finish (Correct answer)
- To clamp the barrel to a workbench for cleaning
- To measure barrel straightness
Correct answer: To securely hold the barrel during barrel removal, installation, or threading operations without damaging the finish
A barrel vise grips the barrel shank securely and without marring while the gunsmith applies torque to remove or install a barrel, or while threading.
Question 3: What is an 'action wrench' and when is it used?
- A special wrench for installing scope rings
- A tool that grips the receiver and provides leverage for removing or installing barrels (Correct answer)
- A wrench used to adjust trigger pull weight
- A tool for removing barrel keys from lever-action rifles
Correct answer: A tool that grips the receiver and provides leverage for removing or installing barrels
An action wrench clamps to the receiver and is used in conjunction with a barrel vise to remove or install barrels by applying counter-torque to the action.
Question 4: What is a 'trigger pull gauge' used for in gunsmithing?
- Measuring the distance of trigger travel
- Measuring the force required to fire a firearm, expressed in ounces or pounds (Correct answer)
- Checking trigger return spring tension
- Measuring the width of the trigger blade
Correct answer: Measuring the force required to fire a firearm, expressed in ounces or pounds
A trigger pull gauge measures the firing force in ounces or pounds to verify triggers are within manufacturer spec or customer requirements.
Question 5: What is the correct driver tip type for removing most American firearm screws, and why does it matter?
- Phillips-head — standard for all firearms
- Hollow-ground (gunsmith) flathead bits that fully fill the screw slot to prevent cam-out and screw damage (Correct answer)
- Torx bits — used on all modern firearms
- Allen keys — universal for all action screws
Correct answer: Hollow-ground (gunsmith) flathead bits that fully fill the screw slot to prevent cam-out and screw damage
Hollow-ground flathead bits are machined to fit screw slots perfectly from base to top, preventing the cam-out that ruins screw heads with standard tapered flathead drivers.
Question 6: What is a 'bore light' used for in gunsmithing?
- To illuminate the trigger group during disassembly
- To illuminate the bore for inspection of rifling condition, cleanliness, and obstructions (Correct answer)
- To check headspace in dim workshop conditions
- To verify proof marks on the barrel
Correct answer: To illuminate the bore for inspection of rifling condition, cleanliness, and obstructions
A bore light is inserted into the chamber or muzzle to illuminate the bore for visual inspection of the rifling, erosion, pitting, or obstructions.
NRA NRA Tools & Equipment for Gunsmithing 1
What is a 'headspace gauge set' and why is it essential in gunsmithing?