Ammunition & Ballistics Flashcards

What penetration depth in ballistic gelatin does the FBI require handgun ammunition to achieve for approval?

Answer: 12–18 inches

The FBI protocol requires a minimum of 12 inches and a maximum of 18 inches of penetration in calibrated 10% ballistic gelatin to ensure adequate terminal performance.

What does 'caliber' refer to when describing a firearm cartridge?

Answer: The diameter of the bore measured in hundredths of an inch or millimeters

Caliber is the internal diameter of the gun barrel, expressed in hundredths of an inch (e.g., .40) or millimeters (e.g., 9mm).

What is the primary purpose of hollow point ammunition in law enforcement use?

Answer: To expand upon impact and limit overpenetration

Hollow point bullets are designed to expand upon contact with soft tissue, creating a larger wound channel while reducing overpenetration risk to bystanders.

What does the abbreviation 'FMJ' stand for in ammunition terminology?

Answer: Full Metal Jacket

FMJ stands for Full Metal Jacket, where a harder metal shell encases the lead core, reducing barrel fouling; it is commonly used for training due to its lower cost.

What is muzzle velocity?

Answer: The speed of the bullet as it exits the barrel

Muzzle velocity is the speed at which a projectile leaves the barrel of a firearm, typically measured in feet per second (fps).

In ammunition terminology, what unit is a 'grain' (gr)?

Answer: A unit of measurement for bullet weight

A grain is a unit of weight used for bullets and powder charges, with 7,000 grains equal to one pound avoirdupois.

What is 'terminal ballistics'?

Answer: The study of a projectile's behavior upon striking a target

Terminal ballistics is the branch of ballistics that studies what happens when a projectile reaches its final destination, including penetration depth, expansion, and energy transfer.