From the early days of my career, I was taught the sequence for the Gatlin gun. Feed, Chamber, Lock, Fire, Unlock, Extract, Eject. I needed to know what the gun was doing for each and every one of those steps. Where is the cartridge, what parts of the guns are involved, why is it doing that, and what happens if parts break right there. It was the first level of whys. Why does the cartridge move this way, why does the extractor catch right here, how does the brass get extracted, and so on. It was the basis of my knowledge that would apply to every Gatlin gun I ever maintained. Then I moved on to maintaining 105MM, 40MM guns, minguns, and .50 machine guns. I realized this same sequence applied to all those guns also. My technique for remembering all firing operations was all based on this memorized gun firing sequence.
Many years later, I started gun training outside the military and realized this sequence applies to each and every gun I have ever shot. Pump action, think about the steps, how does the ammunition get inside the chamber? (Feed, chamber…. Load shotgun shells into the attached magazine on the lower side of the receiver, pump the action which moves the bolt forward and grabbing one shell) Semi-automatic action, think about the steps, how does it feed, how does it chamber, how does it lock, and so on. Same for Bolt action, Hinge action, Derringer, and every single gun I ever had in my hands. These steps are a constant reminder of how each gun works.
Teaching students on the range, I refer to these sequence mentally all the time. What did that gun do? Where did it jam? What step did it stop? I would rarely tell students what step it jammed or how I figured it out rather quickly, but it is always in my head. I do teach those steps in the classroom but I don’t harp on them as much as I do in advanced courses. My thoughts on about this is I don’t want to overwhelm students with the 15 hours of training they already are receiving for the New Mexico Concealed Carry course. I do teach it more in-depth for the Basic Handgun shooting course. It is a foundation of my training that has stuck with me for years.