The gunfighter's dilemma | Hacker News Reader

The gunfighter's dilemma

news.bbc.co.uk

135 pointsvColin60 comments

Apparently, it's incorrect that the winning strategy is to move second - while the drawing motion take ~20ms less when reacting, it takes ~200ms to react in the first place, leaving you quite dead. See http://scienceblogs.com/notrocketscience/2010/02/why_does_th...

Did the BBC misinterpret the data, or did the scienceblogs article make a mistake?

I was just thinking the same thing... the 20ms difference only matters if the start time of the action is less than 20ms before the start time of the reaction.

Just because you can do something faster, it doesn't always mean you finish faster.

Aiming isn't taken into consideration with a button press, so I wouldn't exactly call this study accurate. Bohr did a more scientifically valid test without anything more than a pair of pop guns.

Not necessarily, it depends what causes the defender to draw. It may take you ~200ms to react, however it also takes the drawer time to act on their decision, and may take longer as there's an incentive to aim as there's no point in shooting first and missing.

Button pressing /= drawing and aiming.

The defender has less incentive to aim, and besides your brain already has the calculations made. In hunting the snapshot is a frequent killer due simply to reaction with no conscious aiming. IIRC the NRA has ~40,000 bullseye shooters who have to have rapidfire accuracy on multiple targets to attain the grade. This requires the ability to make snapshots.

I'm not going to believe any result on gunslinging until someone picks up a properly weighted pistol that has to be aimed and fired (whether it be a blank or using an LED sighter). Otherwise it's not scientific, you're fucking with the variables and the very nature of the experiment.

You can't skip the story about Niels Bohr at the bottom.

Niels Bohr should know something about reactions and reaction times - in 1905 he played professional football (soccer) for Akademisk Boldklub, playing goalkeeper.

Seems like a pretty crappy experiment to pit the reaction time of an ex-professional athlete against (presumably) more typical people.

I can't tell if you're joking or not ... are you? Given the context it seems odd that you should interpret the anecdotes as being entirely serious and make such a serious comment, but perhaps I'm just having a sarcasm-detect failure ...

It's dual-purpose. Anyone who thought the article was tongue-in-cheek can assume that I too am being light-hearted. Anyone who thinks the article took Bohr's results seriously can take my comment seriously. Between the dry humor of Brits and the general idiocy of science reporting, I don't think there's any way to tell which is more appropriate.

In a series of mock gunfights with colleagues Bohr always drew second and always won.

Heh... Considering that all the participants were scientists, I'm surprised they concluded that one event caused the other.

Somebody tried making that objection but reviewer N.B. blocked his paper during peer review, citing inadequate references to existing literature. The scientist lost his funding, was denied tenure, and now lives in a van down by the river.

Did he play with Heisenberg? "We knew where both people were, no idea how fast they drew."

I know what you're thinking. "Does the nucleus have six electrons or only five?" Well, to tell you the truth, in all this uncertainty I kind of lost track myself. But being as this is an isotope of uranium, responsible for slow-neutron fission, and would blow your city clean off, you've got to ask yourself one question: Do I feel lucky? Well, do ya, punk?

Hah, this is a trick question; the nucleus doesn't have electrons. And if it blows up, you don't bury the survivors.

Hah, this is a trick question; the nucleus doesn't have electrons.

Well, technically, in an s-orbital there is a substantial, non-zero chance of the electron being inside the nucleus.

Not true, you may have been thrown off by the fact that s orbitals are generally shown as spheres; but the radial extent (probability amplitude) of the wave function goes to zero for small radii, for all s orbitals, see http://www.chem.umass.edu/people/botch/Chem121F06/Chapters/C....

A classically-behaving point particle with the same charge as an electron would drop into the nucleus, but the wave nature of real electrons forbids it. Due to the uncertainty prinicple, there is a nonzero chance of finding the electron in the nucleus, but to say it is substantial is false.

This link to an audio interview was posted previously: http://www.aip.org/history/ohilist/4325.html Gamow talks about meeting Bohr and his wit: He says that he was startled to see a horseshoe nailed above the door to Bohr's house. Gamow asked Bohr why he had it there. Bohr said "I've heard that it works even if you don't believe in it."

There are existing studies which show that people react faster when startled than when not. There's a nifty little online test to check your own response times: http://www.mathsisfun.com/games/reaction-time.html

As far as I know this is the first test to show that startle response extends beyond reaction time, it's an interesting piece of data. It's worth noting that it's possible to force yourself into a state of mind similar to being startled, which may very well eliminate the advantage to "shooting" second.

That game is very telling. Try it at "arms length", then again with your face right up to the screen. See if you don't do much better when the dot fills more of your visual range. Speculation: a startle reflex depends upon the magnitude of the nervous signal, which is larger when more retinal cells fire.

Strange, I had 0.267 with normal measures, and over 0.5 with surprise measure.

I could see this being the case, but it's got to be very narrow timing, and it probably only applies for the same type of action. A friend and I used to do a drill with his Glock 9mm. (After ensuring the gun was unloaded) one of us would point the pistol right at the other's head. The pointee would initiate action by grabbing the gun and the pointer would try to pull the trigger. It was impossible to pull the trigger in time, action was always faster than reaction in this case. We did it many times over, both of us with the gun. Semi-automatic handguns will not fire when you keep the slide from moving, which is what happens when you grab the whole barrel like this, though I don't think I'd be willing to try the maneuver in real life.

From what I remember of KravMaga gun disarms they agreed with your experiments. They taught moving your head out the way at the same time as grabbing.

A Krav Maga gun disarm involves twisting the body while redirecting the shot. Grabbing the gun isn't supposed to prevent the gun from firing, it's supposed to prevent the shot from killing you. In a real life situation when someone's got a gun to your head you probably don't have time to think about the gun's mechanics.

Well thats why you're thinking about it ahead of time.

I distinctly recall the instructors commenting they'd rather face an idiot who gets too close to you with a gun than an idiot who gets too close to you with a knife, the knife will still cut you if you grab it.

They also suggested you comply with anyone who has a weapon unless you have good reason to think they'll kill you anyway.

I Really should take Krav up again, was good stuff.

Yeah, I'm only a yellow belt at my school (Krav Maga Canada has a belt system even though the international org. doesn't) so we haven't gotten into weapon disarms much yet, but I think the general idea is it's easier to give up your wallet than successfully perform a gun disarm or redirect a knife.

Either way, it's a hell of a work out.

A Glock will certainly fire with the slide immobilized. If the slide cannot move with respect to the frame the current round will not be ejected and the next round will not be chambered, but it will certainly fire the chambered round. It is not clear from "grab the whole barrel" what you were doing. Glock is like many (most?) semiautos in that the trigger cannot be pulled when the slide is not all the way forward, is that what you meant? That you could yank the slide out of battery and hold it there, thus preventing the trigger from being pulled?

If you intend to replicate your experiments in the future, you can explicitly seat a snap cap in the chamber and leave the magazine out (no mag safety on the Glock). That way you are still violating rules 2-4, but possibly not rule 1.

It's pretty clear he meant that he was holding the slide back, preventing the hammer from moving forward.

But would that always work on a Glock, which has an odd striker arrangement instead of a traditional exposed hammer, and doesn't have a way to decock it without pulling the trigger?

Holding the slide is not what prevents the hammer from falling. A semi-auto handgun with an exposed trigger that is placed out of battery has its trigger immobilized by mechanical linkage, regardless of the hammer's position.

Because of the way Glocks have their lug linkage, many will actually fire even when slightly out of battery. Knocking the slide back 1/10" and holding it there is probably not going to be sufficient to disengage the lug that prevents trigger pull.

Even if one could manage to pull the trigger with the gun significantly out of battery, I imagine that this would be a non-event with an exposed hammer because as you say, the hammer would fall onto the slide, not the pin. Still, firing out of battery would seem to be a function of the linkages, not striker-vs-exposed-hammer-ness.

"(After ensuring the gun was unloaded) one of us would point the pistol right at the other's head."

Fail. Absolute fail.

We say "the gun is always loaded" even when we "know" it is not, because if we never, ever point a gun at something that we don't want to destroy, we will never make that one in a million mistake.

Fail. Sorry for the forcefulness, but this kind of gun "play" always deserves to be called out and discouraged.

I think you are wrong. I agree with you, in the sense that I would not feel comfortable doing this. "The gun is always loaded" is great rule, as is "Never point a gun at something you don't want to shoot". But it has its limits, and context is important.

Assume that you're a hostage negotiator, or someone in the police or military that otherwise expects to end up in a situation where someone is pointing a presumably loaded weapon at you at close range. I think there's a good argument to be made that you should train for this circumstance under the most realistic conditions you can muster, rather than hoping that your first live experience will go just the way it did on paper. If having a real gun pointed at you helps to simulate and train your real life response, this might be a good strategy.

Personally, as someone not in such a field, I'll spend the bulk of my efforts on figuring out how to avoid such situations. But for a professional training for a situation they expect to encounter, this is not 'play'.

Agreed that there are a small percentage of people who are professionals, for whom the risk of live practice is probably worth the risk, also considering the likelihood that they would have to deploy their skills in this way.

For the rest of us (and I didn't see anything to suggest that these two martial artists were practicing in a professional context), the likelihood of needing to deploy this skill in a real attack is small, and if you want to practice such a skill as self defence you should be doing it with a fake gun, or at most in a way described by novas0x2a's link to the Tueller drill.

To invoke a programming saying, "you ain't gonna need it."

Google "operant conditioning".

I've done so, and think I am generally familiar with the concept. I don't see any direct connection. Could you explain the relevance that you see?

It's why modern militaries prefer to train with real weapons. In the scenario the OP mentioned, it's about getting accustomed to facing a real weapon.

Note that I'm not advocating this for "play", or even amateur martial arts. Someone training for situations in which a real weapon will be pointed at them and they have to remain calm will benefit tho'. (I'm offering evidence to support your point BTW, not arguing with you!)

Professionals are not that stupid to point real guns at their friends' heads. They use special training models which can't actually shoot. http://en.wikipedia.org/wiki/Glock_pistol#Training_variants

I have to second nfnaaron here. The gun is always loaded. I don't care if you just unloaded it. It's still loaded. That's one of the most fundamental gun safety rules. Violating that rule, in my view, means you are not responsible enough to own a gun. I mean, there are really only three safety rules; it's not like there's a huge list.

There are plenty of ways to simulate the exercise with no risk. If you want to do stress exercises, you need to come up with a different way. This[1] is one of the standard ways. Notice that at no point does a real gun get pointed at a human being? That's by design.

1) http://en.wikipedia.org/wiki/Tueller_Drill

Dude, slide immobilized it will still go bang.

Not if the hammer is immobilized by the slide being held racked back

Slide back yes, slide forward no, it is unclear if he knows that & while unlikely could lead to some harm.

>In a series of mock gunfights with colleagues Bohr always drew second and always won.

I'm hoping the author of this article just didn't want to elaborate, but Bohr never thought it could've just been that he was faster at drawing than his opponents? Switching it so he was the first to draw some of the time would have been better design.

This part of the article is most likely intended as a funny anecdote, not as an accurate description of a scientific experiment. Rest assured that Niels freaking Bohr would have thought of that.

And possibly decided that it would be more fun to leave a good story behind and not be seen to loose :-)

So optimally you want to be startled into action by something other than your opponent drawing. Then you get the speed advantage & a head start...

Wonder if anyones done any research on training this for martial arts.

A friend who does Aikido says it's not explicitly taught quite like that - but that he does train to watch, for example, an attackers shoulders for slight movement prior to their attack.

Which implies that you could probably throw off someone like that just by, for instance, feinting the shoulder movement.

My thought to.

Believe me: doesn't work ;)

Having the body control to produce false, seemingly involuntary signals - while suppressing true involuntary signals - implies a level of physical mastery to the extent that you, likely, already possess a substantial advantage in the bout. This is like selling a fake tell in poker while not actually having a tell - even James Bond would tell you that's hard.

You could just sell enough fake tells--produce enough false signals--to throw your opponent off of whatever actual tells you have. I wonder if this is similar in concept to the "drunken" kung fu style.

I don't know any martial arts, but it reminds me of basketball - dribbling is exactly the same - every second you decide to start or not, you can make fake moves, and your oponent has to guess and react faster. And if his guess is wrong he allows you to pass him.

Sometimes you can just feel the rythm in which oponent will react, and then passing him is easy and pleasurable at the same time. And looks cool. That's why I love basketball :)

It's the same in [association] football, rugby, volleyball, netball, [field] hockey. Presumably true in other sports too - so is that really why you love playing basketball?

We had techniques where we try to minimize the "telegraphing" of our own punch. You practice that with a partner, and try to hit the partener's open hand before they can react to it. If the partner notices you moving first, they drop their hand and they "win". Its an effective drill for the partner too, because they have to learn to read your body motion.

Yeah, they do this in Krav and Jitsu too, but it's not what I'm talking about. These techniques are about spotting the initiator as early as possible, then you're startled into re-action.

The article suggests that actions where you're primed to act and then startled into action are faster than ones where you act of your own volition.

So, could you (for example) condition yourself into being startled by say a raised eyebrow, at which point you would be able to carry out a pre-planned attack with the same speed as a reaction.

Kind of like Bruce Willis in Pulp Fiction

So much for first-mover advantage.

The second mouse gets the cheese.

There's always free cheese in a mousetrap.

http://www.youtube.com/watch?v=TANC4VI8vF4#t=1m18s - draws and shoots and returns gun to holster in 0.02s.

I don't feel lucky!

Niels Bohr, liked to take time off from figuring out the structure of the universe by watching westerns.

Bohr noticed that the man who drew first invariably got shot, and speculated that the intentional act of drawing and shooting was slower to execute than the action in response.

Haha, really? So he formed a hypothesis based on movies? I'm fairly sure its just poorly written in the article but if it is not thats just silly.

Edit: Formatting

It would also depend on the first-mover not being adequately trained/experienced. The goal of training, and the effect of extensive experience, is to automatize the action, so that it will occur without conscious intermediation.

Then, since Solo shot first, he was a fine duelist. This reconciles the argument: he can be a good guy AND shoot first. Solo did not _intend_ to shoot first, but while reposting his instincts made him the fastest.

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