What material is commonly used to make the case of a firearm cartridge?

The correct answer is commonly recognized as brass, aluminum, or steel because these materials have specific properties that make them ideal for use in firearm cartridge cases. Brass is the most prevalent due to its excellent corrosion resistance, malleability, and ability to withstand high pressures during firing. Aluminum is lighter than brass and is often used in applications where weight is a concern, while steel is less commonly used but can be strong and cost-effective for some types of ammunition.

Wood is not suitable for firearm cartridges because it lacks the strength needed to contain the high-pressure gases generated during ignition. Plastic is occasionally used in some modern ammunition, particularly in non-reloadable or cheaper options, but it does not offer the same level of reliability and durability as metals like brass and steel. Copper is primarily used in bullet construction, specifically for the projectile, rather than the cartridge case itself. Thus, brass, aluminum, or steel are the preferred materials for manufacturing firearm cartridge cases due to their combination of strength, durability, and performance characteristics.