I have heard it referred to as the cycle of operation, the cycle of fire, the cycle of function, etc. It does not matter what you call it, the cycle of operation of any small arm is illustrated as a cyclic series of eight (8) repeating steps. They are:

• Feeding
• Chambering
• Locking
• Firing
• Unlocking
• Extraction
• Ejectio
• Cocking

Depending on the gun, each of these steps will be performed mechanically (with or without manual input), or manually.

Due to the cyclic nature of repeating guns, the cycle of operation can start at any step. I choose to start at Feeding since the operation of many modern small arms begins or restarts with a loaded magazine being inserted (or an integral magazine being loaded) and closing the bolt (action, slide, etc.). If you are better served by starting at another step go for it.

Let’s look at each step in the general cycle of operation briefly to better understand each concept.

Feeding

Feeding is the act of moving a cartridge of fixed ammunition from its loaded position to a position in line with the bore axis in preparation for chambering.

Chambering

Chambering is the act of moving a cartridge of fixed ammunition from a position in line with the bore axis into a position fully seated in the chamber.

Locking

Locking is the act of immobilizing the action in preparation for firing.

Firing

Firing is the act of transferring energy from the shooters finger, through the action, and causing the detonation of the explosive compound in the primer of a cartridge of fixed ammunition. Firing is not over until the pressure inside the barrel/chamber has reached its natural state.

Unlocking

Unlocking is the act of stopping the immobilizing act caused during the locking step.

Extraction

Extraction is the act of moving the spent cartridge case from the chamber into the action.

Ejection

Ejection is the act of moving the spent cartridge case from the action to outside the action.

Cocking

Cocking is the act of resetting the stored energy in the action in preparation for feeding.

That is it, this series of eight steps will repeat until the gun malfunctions, runs out of loaded ammunition, or the shooter stops actuating the trigger.

Other Things

There are other things to consider when thinking about the cycle of operation. Loading for example. The act of putting cartridges into a magazine, and/or putting a magazine filled with cartridges into a pistol is not feeding. I repeat, putting cartridges into a magazine, and/or putting a magazine filled with cartridges into a pistol is not feeding. Both actions are part of the loading process. Loading is not part of the cycle of operation. Who disagrees with that statement. Based on the responses that I commonly receive at DIY gunsmithing workshops, I am guessing that there are some of you out there.

Think about like this. Do you load rounds into a magazine each time you pull the trigger to fire? No. Do you load a magazine filled with cartridges into the gun each time you pull the trigger to fire? No. Thus. putting cartridges into a magazine, and/or putting a magazine filled with cartridges into a pistol is not feeding. Don’t get me wrong, loading the magazine and putting the loaded magazine into the firearm are important steps in preparing to use a gun, they are just not one of the steps in the cycle of operation. Additionally, there may be other things that you need to understand about the operation of a gun to fully comprehend how it works.

For example, when a modern semiautomatic pistol runs out of ammunition the slide locks to the rear waiting for the shooter to remove the empty magazine and to load a full one. How does this occur? Since it is not part of the cyclic nature of the operation of the gun it is not included in the cycle of operation. However, I recommend taking the time to make sure that you fully understand all the operations the gun performs. It will help you a great deal in the future as you try to diagnose or design around an issue.