Which of the following is a type of ammunition used with the M16/M4?

• A. Ball
• B. Armor-Piercing
• C. Incendiary
• D. Tracer

Answer: (A)

Ball ammunition represents the standard general-purpose round for a service rifle like the M16/M4. It uses a basic full-metal-jacket projectile designed for reliable feeding and predictable performance across typical combat ranges, making it the usual choice for everyday operation and training. The other options are specialized types: armor-piercing rounds have a hardened core aimed at penetrating armor and are tightly regulated; incendiary rounds are designed to ignite targets and are not used for routine infantry work due to safety and limited utility; tracer rounds include a pyrotechnic that lights up in flight to show the bullet’s path, which can reveal the shooter’s position and is used selectively. Because of its standard, non-specialized nature and broad applicability, ball is the type commonly used with the M16/M4.