NRA NRA Ammunition & Ballistics

Question 1

What are the four components of a centerfire cartridge?

Accepted Answer

Bullet, case, primer, powder

Answer

A standard centerfire cartridge consists of a bullet (projectile), a case (brass or steel), a primer, and propellant powder.

Question 2

What is the difference between a boxer primer and a berdan primer?

Accepted Answer

Boxer has a single flash hole and self-contained anvil; Berdan has two flash holes and relies on an anvil in the case

Answer

Boxer primers are self-contained with an internal anvil and a single central flash hole, making them easy to reload; Berdan primers use two off-center flash holes with the anvil formed into the case.

Question 3

What does SAAMI stand for and why is it important to gunsmiths?

Accepted Answer

Sporting Arms and Ammunition Manufacturers' Institute; it sets industry standards for chamber and ammunition dimensions

Answer

SAAMI (Sporting Arms and Ammunition Manufacturers' Institute) establishes the dimensional and pressure standards that ensure safe interchangeability of ammunition and firearms.

Question 4

What is the primary difference between rifle powder and pistol powder in terms of burn rate?

Accepted Answer

Rifle powder burns slower; pistol powder burns faster

Answer

Rifle powders are generally slower burning to build pressure progressively over a longer barrel, while pistol powders are faster burning to achieve peak pressure in shorter barrels.

Question 5

What is sectional density (SD) of a bullet?

Accepted Answer

The ratio of bullet weight to its caliber squared, indicating penetration potential

Answer

Sectional density is the bullet's weight (in pounds) divided by the square of its diameter (in inches), and higher SD generally indicates better penetration.

(NRA) National Rifle Association Certified Gunsmith Practice Test

(NRA) National Rifle Association Certified Gunsmith Practice Test

NRA NRA Ammunition & Ballistics