NRA Ammunition & Ballistics Flashcards

What are the four components of a centerfire cartridge?

Answer: Bullet, case, primer, powder

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

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

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

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.

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

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

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

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

Answer: Rifle powder burns slower; pistol powder burns faster

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.

What is sectional density (SD) of a bullet?

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

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.

What is a Magnum cartridge generally characterized by?

Answer: A larger case capacity resulting in higher velocity and energy compared to its standard counterpart

Magnum cartridges are generally characterized by larger case capacity, which allows more powder for higher velocities and increased muzzle energy compared to standard cartridges of similar caliber.