TLDR: Despite how it might benefit a fictional scene, it’s extremely rare for a gun to off accidentally, even when it’s dropped. It’s far more likely the “accident” is due to negligence.

I have great luck with my push lawnmower. It’s old, missing a few bolts and requires just the right touch to operate, but it gets the job done. If I’m lucky, it’ll start before pull number three. If it doesn’t, I know there’s a mechanical error. I might not know exactly where, but I follow a logical path to find it. Is there gas in the tank? Is the spark plug throwing a spark? Is the throttle adjusted correctly? Is there grass preventing the blade from spinning?

I know to follow that diagnostic path because my lawnmower only runs if certain things happen in a particular order. If they don’t, the lawnmower won’t work.

The same could be said of firearms going off by “accident,” such as by being dropped, no matter how convenient that is to the plot. The old axiom is true: there are no accidental shootings, only negligent ones.

The Trope: A Gun Goes Off When It’s Dropped at a Critical Moment

Although the “accidental” shooting trope materializes in fiction in many ways, the “gun drops on the floor, goes off and shoots characters” version is the most common. Witness the following offenders:

Why Guns Don’t Go Off Accidentally When Dropped

This trope supposes a gun will fire unintentionally if its ammunition and other components are rattled hard enough. If this were true, why wouldn’t the gun fire on its own after the first intentional shot? Recoil is a lot more potent than a three-foot free fall to the floor. Except that doesn’t happen, because this trope is BS.

Just like that lawnmower, firearms and the ammunition they use are designed to work one way and one way only. The act of pulling a trigger causes a firing pin to strike the primer at the base of a cartridge. The primer ignites the propellant inside the cartridge. The propellant explodes and forces the bullet seated at the top of the cartridge to exit the barrel. The end.

Yes, the details of that process change depending on the firearm and the ammunition, but it’s the same dance, different prom. Dropping the gun on the ground doesn’t change anything.

Some manufacturers even use a designated safety system just in case the gun is dropped. Glock pistols, for example, sport a drop safety. This is less an admission and more of a design requirement given Glock’s passive safety systems.

The Exception: A Mechanical Failure

The exception is a mechanical failure. If some piece of the aforementioned process is out of whack, sure, it’s possible for a gun to go off if dropped. This article by Massad Ayoob explains this in detail better than I could:

Usually, the culprit is a phenomenon called “inertia discharge.” It occurs with, say, a semi-automatic pistol whose firing pin “floats” in its channel without a mechanical lock. If the gun is struck sharply in a direction parallel with the pin’s travel in that channel, it can come forward enough from inertia to discharge. This may occur if the gun is dropped on its muzzle, in which case the bullet generally strikes what the muzzle hit and causes little damage unless it has hit a second-story floor in a multi-floor building, in which case the bullet can pass downward through the floor and into the room below. It may also occur if the pistol is dropped on the rear of its slide or receiver, the spur of its hammer, etc.

What Ayoob describes is rare, and would be most common with older guns containing worn parts. Even then, what he describes would only allow the gun to go off a single time. I’m sure it’s happened before, but the odds of consecutive shots are miniscule.

“Accident” is Another Word for “Negligence”

So what gives with all the stories in the news about guns accidentally going off? I’ll let you in on a little secret, dear reader: none of those stories were about accidents. Ninety-nine percent of the time, the person with the gun screwed up and unintentionally shot someone. That, unfortunately, is negligence. To say otherwise is to say that water in a pot comes to a boil without turning the stove on, that shoelaces untie themselves in order for you to trip on them and that donuts eat themselves while you’re supposed to be on a diet.

Negligence can take many forms, such as:

• The shooter pulls the trigger without realizing it.
• The gun is left loaded in an unsecured area where someone else finds it and pulls the trigger.
• The gun is not stored or holstered in a safe manner.
• The gun is not operated correctly during loading or unloading.
• The person handling the gun is generally an idiot.

Sure, the person pulling the trigger might not intend to do so, but that doesn’t put the bullet back down the barrel. This is why there are basic gun safety rules. Projectiles are unemotional, uncaring and stupid. They can’t think for themselves. Neither can the firearms. Only the shooter can.

People claiming “accidental” shootings are covering their keisters for their inevitable court date. Pay attention the next time an accidental shooting pops up in the news. Is it truly an accident? Or is negligence the more likely culprit?

Still Not Convinced?

For a closer look at this concept in action, watch this video from YouTuber Skallagrim (and then subscribe to his channel, it’s a good one). He demonstrates why true accidental shootings are rare with an AR-15 on his lap. Can’t beat that.

The Takeaway for Writing Fiction

If a gun must absolutely, positively go off when dropped in a scene, follow these pointers:

• The gun should be at least 30 years old or have some obvious mechanical defect.
• The gun should be loaded and have a cartridge in the chamber, ideally with the safety disengaged.
• The gun should only fire one time when dropped.
• The gun should give a wisecrack when it hits the floor, like, “I guess you really dropped the ball with that one, didn’t you?” (optional)

For everyone else, I formally challenge someone to write a scene where a gun is dropped and doesn’t go off. The character picks it back up and says something like, “Thank goodness this thing doesn’t work like in the movies.” You win the gold star.

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