Which of the following is NOT part of the cycles of function for the M4/M16 series rifle?

The correct answer is "Cleaning" as it is not part of the operational cycles of function for the M4/M16 series rifle. The cycles of function for these rifles focus on the mechanical processes that occur during firing. This includes feeding, where a cartridge is loaded into the chamber from the magazine; ejecting, where the spent cartridge case is removed from the chamber; and chambering, where a new round is loaded into the chamber after the firing process.

While cleaning is certainly an essential maintenance practice for any firearm, including the M4/M16, it does not occur as part of the firing procedure or the operational mechanics of the rifle itself. Instead, cleaning is a separate process performed to ensure the firearm operates reliably and safely over time. Understanding the distinct roles of operational cycles versus maintenance actions helps in effectively managing and utilizing firearms.