Reddit/r/firearms.

Let me first start by saying that the clearing procedure I followed would have been correct for almost every firearm you encounter on a regular basis, and due to following the four basic rules of range safety, no one was injured. In fact, I was the only person to even notice the discharge. I was still at fault, I should’ve handled it differently, but I was with a large group of people on a deadline, and went into autopilot.

My range has a collection of post dealer sample machine guns. From Kriss Vectors to FALs to AKs to Uzis. This particular incident was with a mini-uzi with a suppressor. For those of you who aren’t aware, the full size and mini uzis fire from an open bolt. The round fires as soon as the bolt chambers a round, as opposed to more common closed bolt systems where the firing pin is actuated separately from the bolt.

So, in the process of a machine gun shoot with tourists, one experienced a failure to feed. A round partially made it out of the magazine but not to the bolt. The next round had tilted and blocked the bolt from moving forward. Usual procedure is to remove the mag, rack the action and remove the round. However, in an open bolt system, you are supposed to rack the bolt back first. This is where I messed up. Upon me removing the magazine, the bolt slammed home with the hung round and fired.

The weapon was pointed downrange, as always. No other safety rules were violated aside from my mental lapse of the particular operation of the gun. In fact, I was the only one that noticed. Between it being suppressed, and multiple other people shooting, it was lost in the background noise. I did however take it as an opportunity to point out my mistake and teach the customers why the four cardinal rules are important, no matter how experienced you may be.

Well, you won’t see me laughing, poking fun, or criticizing him.  He knows what he did, he used it as a learning opportunity, and he followed the rules of gun safety.  Good for him.

But there is this comment.

The Swiss Cheese model of accident causation is a model used in risk analysis and risk management, including aviation safety, engineering, healthcare, emergency service organizations, and as the principle behind layered security, as used in computer security and defense in depth. It likens human systems to multiple slices of swiss cheese, stacked side by side, in which the risk of a threat becoming a reality is mitigated by the differing layers and types of defenses which are “layered” behind each other. Therefore, in theory, lapses and weaknesses in one defense do not allow a risk to materialize, since other defenses also exist, to prevent a single point of weakness. The model was originally formally propounded by Dante Orlandella and James T. Reason of the University of Manchester, and has since gained widespread acceptance.

He can call it whatever he wants, but in legal parlance (e.g., with various government entities like the NRC) it’s called “defense in depth.”  Don’t use the phrase “Swiss cheese model” of safety.  Call it what it is – defense in depth.  We’ve discussed it many times here on the pages of TCJ.

I’ll also take a moment and repeat what we all know and what I’ve said many times.  When a LEO points his weapon at someone, he is violating the most important rule of gun safety and using the most important margin in the concept of defense in depth.  But it’s okay because he is a LEO, and God knows, they all need to go home safely at the end of their shift.  There’s nothing more important than that.