What does the internal ballistics component in firearms refer to?

The internal ballistics component in firearms refers to what occurs inside the firearm during the firing process. This includes the ignition of the propellant, the generation of gas pressure, and how these elements work together to propel the projectile down the barrel. Understanding this component is critical for comprehending how different factors—such as the type of ammunition, the firearm's design, and the physical characteristics of the barrel—influence the performance of the firearm.

In contrast, the other aspects focus on different stages of the firing process. The flight of the projectile after it exits the barrel pertains to external ballistics, while the interaction between the projectile and the target relates to terminal ballistics. The processes happening after the projectile has left the firearm are vital, but they fall outside the scope of internal ballistics, which is specifically concerned with events leading up to and including the exit of the projectile from the barrel.