I completely agree. Lots of stuff can happen.

The point is that the only type of shot that incapacitates people reliably is a CNS hit. Torso shots might stop an attacker rushing (and the chance is a lot higher than him tripping), but there's a very good chance it won't. The conclusion is that your response has to factor in that even when you double tap him COM, you're still going to have to handle his charge - move sideways so he can't build momentum, get obstacles between him and you, stay out of his range, prepare for melee. It is a VERY bad move to just stand your ground and fire your weapon, mistakenly feeling confident that you will stop him in his tracks.

Because people only very rarely trip over their own feet. Certainly not something I'd rely on if a guy was charging me with a knife.

Fixed for you. Your problem seems to be that that you consider the human body to be the equivalent of a solid, immovable object like a block of concrete, which can only be moved or toppled over with a clearly defined force applied at a certain point/angle. The reality is a _bit_ more complex, which is why walking upright is such a complicated excercise.


Moved on? That was my point from the beginning, and apart from some ridiculous strawmen with "kinetic energy counters" and accusing me of hollywood science, your stopping power against this point has been kinda limited. Pretending that it is an all new point which I only came up with after you blasted some other imaginary claims makes your arguments even more pathetic.

I'd say you watched some Discovery Channel show about snipers which basically said "to immobilize somebody you need to take out the CNS or cause a hemorrhagic shock" and now feel you have all the answers. Too bad you don't really have understood the underlying mechanics, just "science says this, I'm right, fuck you", so now you are trying to apply this knowledge to everything which is somehow might be connected to terminal ballistics.

Oh, and when are you planning to finally answer my question?

Ok, if your point all along was that the force of the impact is what knocks people down, by simply toppling them, that's still wrong. It just doesn't happen. The forces involved in relation to the momentum of the human body is just WAY too low - and shooting someone in the chest is pretty much center of mass, the point where you have the least chance of toppling someone.



I was a soldier, and I'm a hunter. I took advanced physics and graduated with an A+, which gives me an adequate understanding of mechanics. I probably also watched some discovery show about snipers, and I'm able to search the web and read. Each and everyone of those areas yields the same answer: people don't get toppled over when hit by bullets.



If someone runs past me and I catch them with a hook to center mass, you slow down the runner a bit. If I'm standing in the way and throwing a straight to center mass, pretty much the same as if he'd run into my straight arm, except it would be harder on my arm. A forearm strike (or a hook with lots of body behind it), somewhere in between. Overall, going for center mass at someone running, it might slow him a few percent by punching, but it certainly won't stop him - for that you need to have your body mass behind it and then you're looking at what is basically bracing against a tackle.

Posting credentials in internet discussions is pointless, since you cannot prove them anyway. What counts are sound arguments.


And why does it do that?
a) blood loss
b) pain
c) CNS failure

And remember, any other options are invalid unless you want to go into "physics fairy land" or "hollywood science"...

You brought up my credentials, not me. When you say I'm getting my opinion from discovery channel, I'm going to reply with where I'm coming from.




It is a matter of scale. Obviously there is momentum in a bullet and a punch, and this will affect someone getting hit. But the momentum (especially for the bullet) is so low that it hardly has any effect, especially when directed at center mass.

The "physics fairy land" and "hollywood science" comes in when you claim that the same exagerated effects we see in action movies apply in real life. It doesn't. Getting hit by a bullet won't topple you anymore than the recoil from firing the weapon topple the shooter. Getting hit by a punch while running will stop you dead in your tracks as little as throwing one against a stationary target sends both puncher and target careening off in opposite directions.

http://www.youtube.com/watch?v=aaS_2l8nGdg

At 2:15 a guy in body armor gets shot while standing on one foot by a 7.62x51 NATO round. He doesn't get knocked down. That really should answer the knockdown-power argument.

Uhm, you accused me of getting my info from hollywood and fairytales


Trying to evade an answer? Come one, only three options, it's not that hard...

Well, just name-calling back doesn't really correct that does it? You're very welcome to tell me where you get your info from. I can deduct that you're not getting it from real world experience or any understanding of physics, so I presumed movies and fantasy.



I provided a full and complete answer. As I've said all along, there is a transfer of momentum, and it has nothing to do with the 3 options you listed. The problem is that it is very small - you're AT LEAST an order of magnitude wrong for the effects you talk about to occur.

I see it a lot from people that have a superficial knowledge of science while never really having dug into the subject. They don't appreciate magnitude. Physics is a hard and accurate science that provide very clear boundaries for what is possible and what is not.

If you take a 13g .45 bullet travelling at 330 m/s, it has a momentum of 4.3 kg m/s. A 75 kg man running at 7 m/s has a momentum of 525 kg m/s. That's a 0.8% reduction in speed per hit - you're not going to topple anyone with that. Not that you had to do these calculations, you could simply imagine a man running while firing his .45 ahead - you wouldn't expect that to slow or topple him, would you?

A 3kg forearm coming at 8 m/s has a momentum of 24 kg m/s. That gives an 8.2% reduction in speed, assuming a non-elastic impact. 5 times as much as the double tap, but still not enough to stop the guy.

Have you watched the video Waya posted? Do you think it is fake, since it clearly proves you wrong?

There is also something like this
http://en.wikipedia.org/wiki/Stopping_power#Knockback
Although popularized in television and movies, and commonly referred to as "true stopping power" by novice or uneducated proponents of large powerful calibers such as .44 Magnum, the effect of knockback from a handgun and indeed most personal weapons is largely a myth. The momentum of the so-called "manstopper" .45 ACP bullet [...] is simply incapable of arresting a running target's forward momentum.
[...] knockback is not possible with a handgun bullet

That's some solid calculations, there's real world footage, there's links to wiki.


Please, Sengir, present something, anything, that supports your idea that the "force of the impact" of a bullet will stop someone charging you.

Not that anything on wiki is guaranteed accurate, but the math doesn't lie. If you want to knock someone over, hit them with a mass greater than their own. Might I suggest a car?

Humans are both fragile and difficult to kill at the same time. The most effective ways to kill are to disrupt the CNS (crashing the CPU) or to cause exsanguination. Even with massive trauma and blood loss a determined attacker can keep going for several minutes until the brain starves from oxygen deprivation.

As stated earlier, most one-stop shots are psychosomatic. We are socialized that a bullet kills instantly, so our minds often make it so.

This was your orignal answer converning momentum and KE



A simple experiment: Jog next to somebody, and when he does not expect it shove him forward slightly. Even tough the relative momentum of your arm is close to neglectible, the subject of our practical experiment will still most likely hit the dirt, while the equally strong "recoil" will not make you do the same. And if a deer gets shot while running (and does not roll over right away), it will still stumble for a few moments before running off even though a practiced shooter will barely flinch when firing.
Like I said earlier, the human body is not a statically determinate solid system, where you can simply calculate which forces apply and decide if the structure falls over. Especially not when we are moving forward on our hind legs

I fail to see your point? In that post I wrote KE didn't matter (except for the obvious correlation to the extent of injuries), and I stand by that. I didn't write "the bullet doesn't transfer momentum", just that the amount of momentum is in no way significant relative to stopping the attacker.



So you propose you can shoot someone in the back when he's charging you?

Because the problem with your example is that for someone running, push them in the back so they go off balance, gravity will work to pull them further off balance - it is an unstable system. A push from the front will also put them off balance, but here gravity will work to pull the runner back into balance - it remains a stable system.

A shove also carries a lot more momentum than a bullet.


I asked it before, and I'm getting very curious - where is it you have this understanding of the effects of bullet impacts from? Have you seen documentaries or read about it? Shot anything living? Shot a weapon at all? I'm guessing you have no solid info or experience at all, which is why I think it is fascinating that you keep on defending your position. You have no idea of what you're talking about, yet you keep on digging a deeper hole for yourself. Wouldn't it be easier to just be open to the idea that someone knew something you didn't, and only have to wrong once?

If you prefer elbow the guy into the front, or have some drunk charge towards you and greet him with a punch. The result will always be the same, the target is thrown off balance and stumbles - which is just what you want when somebody is coming towards you with a knife.


I said "shove him slightly", not "do a rugby tackle"


Hm, mister science asks for unverifiable claims of annecdotal evidence? Y'know, whenever I want to give up on this topic you come up with another fun fact

If a single punch is going to make somebody stumble under any conditions other than a sucker punch from behind then you either throw a punch that none of the black belts I work out with can match or you know some weak drunks.




Let's say you shove somebody at an incredibly slow 1 meter per second. Let's not even factor in that a shove is going to use more than just your arms and use Smokeskin's 3kg estimate for an arm. 2*3kg * 1 m/s= 6 N/s. Assuming you are wearing a vest that can stop a .45 acp round is .015kg*250m/s= 3.75 N/s. In other words, a light push imparts almost twice as much momentum as the bullet. Even so, most people will stumble a couple of steps and then regain their balance and keep going from the shove even if they aren't under the influence of adrenaline.

That hardly always happens - I'd say rarely even. And you're talking about punching, which by the numbers above carry 10 times more momentum than a .45 bullet.





A rugby tackle would carry over 100 times the momentum of a bullet - there's ample room between the two for a slight shove to be less than a rugby tackle and more than a bullet.

And if you are really thinking about something the level of a bullet, why not just use the example of a jogger firing a pistol? Then you'd be saying that someone jogging and shooting a pistol would fall over from the recoil, which is obviously ridiculous, even if it came as surprise.



So you're saying that you position is actually an unverifiable claim? Even though I'd say it was easily falsifiable, if you're presenting unverifiability as a defense of your opinion, you're out of reach.


Bottom line is, you have done zilch to back your claim of what hits to the chest do, except display a blatant ignorance of the mechanics involved (for example with your constant comparisons to punches and shoves that are an order of magnitude above bullets in terms of momentum).

When fighting you normally are in a stable position with a lower center of mass and tense muscles. A running person will already kiss the floor if a floor tile is two centimeters lower than the rest and this "hole" is not noticed before. Walking upright is a highly complicated affair, and even small disturbances screw up the whole system.

@Smokeskin: Maybe look up what this strange thing called "annecdotal evidence" is, it might help you understand that sentance...

As for the sniper rifles = CQB thing, we ruled that once you get into range of a melee weapon or unarmed attack it swaps from the firearms skill to the other combat skill being used. It's a lot harder to "just shoot someone" when they're punching you in the head than most people believe. We did, however, add a Martial Arts technique that would allow you to ignore this effect. It did a great job to help balance things a bit for adepts and forced the combat guys to expand their skills a bit to more closely reflect the reality that gun skills really aren't the one and only answer in combat.

"Cop Killers"... Load me up some for Shadowrun I say... Hell, they made AV ammo look weak...

Keep the Faith

.

Dude, a simple shove transfers a hell of a lot more force to the target than a bullet does.

Note that I sad "transfers", not "has".

It is true that a bullet has considerable force behind it. It is, however, acting across a much smaller area than a hand would be.

The idea that a bullet hitting someone will all by itself knock someone down with the power of it's impact is, in fact, just pure hollywood fantasy.

On someone who is unbalanced, you MIGHT be able to cause the guy to trip if you hit him in an unstable spot like his legs, but that's not the force of the bullet making him fall down, that's gravity and his own momentum doing the job.

Someone running straight at you, hitting him center mass will have next to zero effect.

Hell, a LOT of folks that get shot don't even realize it's happened till some time afterwards, the adrenalin rush of combat alone will mask feeling the impact force.


-np

If you are talking about force (as opposed to momentum) than no, certainly not. O(v^2)...



..and when somebody dies from a shot wound the bullet itself is not responsible for the death, but the blood loss or damage it caused...does that mean bullets don't kill people?

Sengir, instead of nitpick at a few minor and irrelevant points, how about you comment on some of the relevant stuff instead?

PS: As KarmaInferno stated it, his comment about transfer of force was poorly worded, but the heart of it was real enough - if we assume that the shove and the bullet both affect a change in momentum over the same timeframe, the shove IS done with a lot more force. And force is certainly not O(v^2) - force is totally unreliant on the magnitude of v, this is pretty much the basis of the whole moving frame of reference thing. I think you're confusing kinetic energy and force?

Like your idea of runing humans as rigid structures moving on rails? Or your wish for unveriafiable war stories providing some annecdotal evidence? Well, if you wish I can come up with dozens of real or imagined stories to prove my point and claim any credentials you like, because that would be so scientific...



And if a body with a certain kinetic energy collides with something else (without deformation and anything) the energy does what...?

It depends upon the impacted body... assuming no deformation like you indicated, if the body collides into something that is solid enough to STOP the body, the all kinetic force is then imparted to the object. However, if the object is not solid enough to stop the body at all, and is in fact minimally resistant, thebody will pass through the object with little residual damage to the object, as the remaining Kinetic Energy is spent on something esle other than the Object. Now, if the Body and teh object fall somewhere in the middle, some of the kinetic energy will be imparted to the object, and depending upon how resistant that object is, more or less of the Kinetic Energy will have an effect...

In relation to Forearms... the best round would be powerful enough to penetrate body armor, using little of its Kinetic Energy to do so, and yet not over penetrate the person wearing the body armor with all the force of the remaining Kinetic Energy being dissipated within the body of the person... note that this is rare occurrence... Pistol rounds against good body armor tend to not penetrate the armor at all... when they do, they generally have more than enough energy remaining to pass through the body into the back armor, unless something critical happens... and then High Velocity Rifles (as in most common Rifle Cartridges) are just way overpowered to impart all of their energy on the impacted body, as they generally spend most of their energy on the landscape after passing through...

And then you have freak accidents:
I think I related the story of the shooting that happened on the Base I was stationed at. Guy, wearing body armor, gets shot with a .45 slug. Unfortunately for him, it enters his body from teh left and passes through his left arm and into the chest cavity, where it bounced off of his rib. at that point the slug passed through the front and back of his chest cavity 4 times, impacting the body armor on front and back, before exiting his torso through his right arm (They found the bullet in the passenger door next to him)... So, sum total of the number of holes in this poor kid... 2 Left Arm, 6 in the Chest (2 Front, 2 Back and 2 left/right), and then 2 Right Arm... Total of 10 holes in the body, from a single slug. Notice that the slug could not pass through the armor at any point (it entered between the front and back plates on the left and exited through the front and back plates on the right, and never once actually penetrated the vest itself front to back, though it should have been "caught" by the armor plates once it impacted one, this did not happen, as none of the plate impacts were straight on, but angled)... The vest would have stopped the round had he been facing in the direction of the bullets travel. As it was, both of his lungs were, for the most part, destroyed and his heart was pulped... he survived long enough to talk to his comrades as they rushed him to the hospital (he was not moving of course) and he died 45 minutes later, regardless of the steps taken to keep him alive (Hard to live without functional lungs and heart, plus a myriad of other severely damaged organs).

Point is... Pistol rounds are generally less than optimal for taking someone down who is wearing body armor, unless you are using superior ammunition and their armor is not so good. Rifle ammunition tends to over penetrate more often than not and expend their energy on the environment rather than the person targeted... There are many documented cases of unarmored individuals taking many multiple hits from both pistol and rifle rounds (both in war time and in civilian circumstances) and still keep on coming... anecdotal evidence maybe, but evidence nonetheless, and easily verifiable.

On a more personal note... when my father was a cop, he shot a guy several times who was closing with him with a knife, using a Colt 45 (ended up with 4 shots COM), and he still sufferred the ignominy of taking a knife to the side before the assailant went down for the count... these things can and do happen, so you should always be prepared to deal with such a situation, rather than believe that your Double tap to the Chest will be good enough...

Just Sayin...

keep the Faith

Sure, just like there are many documented cases of people who took a single shot and basically were out before hitting the ground.

The question is which of these two extremes is closer to being the exception. Given that such discussions always yield the same two or three "he just kept coming" stories and that the standard tactic for such confrontations still is a double tap instead of "run and hide" I'd say the answer is kinda obvious, but oh well...


And so that Smokeskin is satisfied, here's some annecdotal evidence: The German police used FMJ rounds until ~2000, because for a long time the police was planned to be used as reserve troops for the day Ivan would come walzing through the Fulda Gap (heck, until the 70s the average beat cop was trained on the MG 42 and the federal police still is technically allowed to use hand grenades). Anyway, in 2000 the police union and several politicians were lobbying heavily for new ammo, with several examples of the old rounds failing to stop someone, or innocent bystanders getting hit due to overpenetration...but the interesting thing is that it always were the same two or three stories making the rounds. Even when talking to officers you just heard the same stories.
Now if the unstoppable zombie charge is the rule, how come even with the crappy old FMJ rounds there so few known cases? Granted, we have less than 20 people lethally shot by police each year and German FOI laws are a joke, but if dropping someone with FMJ rounds from a hnadgun was that hard there should still be far more known cases.

And this after I specifically noted that I'm not talking about how much total pushing force that the bullet posesses, but only the amount that gets transferred to the human body on impact.




Well, TECHNICALLY most coroners DO actually put "cause of death" as "blood loss" in cases where someone has bled out.

But that aside, your analogy isn't the same thing as the bullet knockdown thing. The bullet killing the person is entirely the cause of the bullet. There was no existing condition it exacerbated. It's not like the guy had a hole 90% of the way through his skin and the bullet just opene up the last 10%.

I'll use another analogy of my own. Let's say you have a barrel full of water. If you poured in another cup, technically I guess you could state that you made the barrel overflow. But the main reason it overflowed was because it was full already. If it had not been full there is no way that cup of water you poured in by itself could overflow it.

Heck, let's just forget about the amount of kinetic transfer for a moment. Even if we assume 100% kinetic transfer, there is at MOST the same amount of force hitting the target as there is pushing back on the shooter. Most shooters aren't getting knocked on their asses every time they pull the trigger. A bullet might provide that last "cup" of unbalancing force enough to drop someone already unbalanced, but it's not going to knock down by itself.

This assuming the bullet's force is striking in a manner that somehow increases the unbalance, and not getting simply negated because it's pushing in the opposite direction the target is moving


-np

So sometimes a guy drops from first shot, and that leads you to believe it is a good tactic to bet your life on it?



The standard tactics isn't double tap in that situation. It is "keep shooting". And I can't imagine there is any shooter receiving tactical training that isn't taught that even lethal wounds will often take 10+ seconds to actually incapacitate the target. You shoot as he charges you, preferably while moving sideways and/or behind an obstacle, and if you can't get out of the way, prepare to receive the charge. Saying the standard tactic is "just double tap" is sooo wrong.

I admit I don't know how the German police is trained, but what you're describing goes against everything I ever heard of.



Who says there aren't more known cases? Just because the 3 best stories gets presented in the news, that doesn't mean there aren't others. And how often is the police charged by armed criminals?

You can't draw conclusions from what stories the news choose to quote. You could also wonder WHY the police was lobbying for harder hitting bullets? Because they're guncrazed maniacs? Because they think too many of their targets survived? Or maybe they were observing real problems that it took too long for their targets to go down?

Force would be F = m dv/dt. If the round simply gets slowed to zero velocity, this means that a bullet at 300 m/s would result in 50% more force than the same bullet at 200 m/s.

But v^2 is 2.25 times higher for the fast bullet, 125% more! F is clearly not O(v^2).

You can't make your "F is O(v^2)" work. It doesn't fit with the formulas. F is O(dv/dt).

You could make a case for force being O(v) under certain assumptions (like end velocity 0), but O(v^2) doesn't hold.

Have you even looked at a single formula in attempting to defend your false claim?

Because Sengir isn't going to look down a few lines when it hurts his myth of a reliable single shot stop, it should be pointed out that the standard tactic is more "keep shooting while moving laterally until the threat is neutralized." Neutralized of course has different meanings based on the situation.

I wonder how many shots the average strawman takes before htting the ground...


If you claim that the relentless zombie assault is the standard case was true that still sounds like a really stupid plan. If the target takes >10s to stop charging you the smart tactic would be "shoot him once or twice and then RUN LIKE HELL until he bleeds out".



You brought up annecdotal evidence ("the guy in the video keeps standing, I'm right"), so here you have annecdotal evidence, too. If you have a randomised double-blind study, bring it on...


Which part of "Even when talking to officers" is unclear to you?



Oh great, a true believer...


AS far as the physics go:
The work-energy theorem tells us that the work required to slow a moving projectile with mass m and speed v₁ down to v₂ equals the difference in kinetic energy:

W = E₂ - E₁ = 1/2m (v₂² - v₁²)

If we want to stop the projectile completely this gives us

W = 1/2m (0² - v₁²)

Finding out about the relation between W and F is left as an excercise to the reader...

Since I happened to come across it again:

http://webpages.charter.net/riffmonger/pho...fectiveness.pdf

That's a non-classified FBI document on handgun effectiveness. It's an interesting read in general, but the pertinent part is on page 12.

Wikipedia incorporates some of that information, but not nearly enough. Still, you can find all manner of data about the effect a bullet makes on the person: impact, holes, cavities, something that amounts to 'time of stagger', etc.

Maybe you think it is a stupid plan. Nonetheless, keep shooting while moving sideways and/or getting obstacles between you and him is believed to be the best tactic. Are you seriously going to keep up this "the entire tactical community is stupid and I'm smart" act?





You are thinking of W = F d?

Apparently you assume displacement is not correlated to velocity. This is not correct.

You are forgetting that we are looking at the average force over the same time period. With a uniform force over the same time period, the distance needed to slow the bullet becomes O(v).

Thus while W is O(v^2), and F and d are both O(v).


Just for fun, let us assume you were correct. That would mean that F = m dv/dt was wrong, as that was the basis of my calculation! I mean, really, do you ever think before you post?

You know what the word "if" means? Try googling "reductio ad absurdum"...

This is because 1) the mass of the gun is incredibly huge compared to the mass of the bullet, 2) the force acting on the gun is partially redirected so that it isn't perfectly opposite the force acting on the bullet.

What do you mean by O(v) -- no specific physics term comes to mind.

http://www.youtube.com/watch?v=QCzD5uhSViY -- revisited Knockback? Probably not. Knockdown? Think about what happens when a person gets tasered: http://www.youtube.com/watch?v=Z-SUDGWFVw4 When you take a good amount of damage, I have no problem with a person falling down. I think the knockdown rules as written are just fine.

Ditto. Also, bored of the fighting.

If you need to tone it down in *your* game, add 1 to the number of boxes required or something; remove it altogether if it's a problem. The game is not real, nor even realistic. It's an abstraction loosely based on reality and movies.

I'll restate.

The amount of force transferred to a person by a bullet is NOT sufficient by itself to overcome that person's inertia. Even if you multiply that force by 10 it would not be enough.

You mention the mass of the gun. Well, the mass of the target is a LOT more than the mass of a gun.

If you see someone fall down after being shot, he is NOT falling down because the bullet knocked him on his ass.

He is falling down either because of critical system damage, or he was already unbalanced and the shock of being perforated tripped him up.

(Or possibly he mentally can't deal with being shot and his knees go weak, in which case he's also possibly curled up in a fetal position crying with a spreading yellow stain on his pants.)


-np

Personally, I like the spirit of what the knockdown rules are trying to accomplish even if I don't particularly like the execution. After all, one of the commonly cited flaws of hit point systems is the way characters can remain so bloody effective right up until the point they keel over and die-- I like the idea of characters being nearly or very nearly incapacitated without necessarily being unconscious. Wound modifiers combined with the Body+Will test to stand back up while wounded go a long way towards rectifying that situation, of course, but there's still the weird outlier situations out there when characters are suffering bad penalties but never actually get knock downed so they still continue to function pretty well in their area of expertise.

For example, I once had a Low Pain Tolerance Elf Samurai facing serious penalties due to a combination of having been beaten earlier in the session and later being exposed to tear gas for a few combat turns. If he had been knocked down at any point, he literally would have been unable to get back up without using Edge or getting help from an ally, but since he never actually got knocked back down by any one single attack, he was still tossing around 8 dice to shoot and still could move around just fine as long as he didn't try a sprint test. Now, it'd hardly bother me if toughness had been something in this character's wheelhouse, but like I said, he had LPT and was using Will as a dump stat-- The player actually sorta saved the day from a role playing angle on this and willingly had his character get the hell out of Dodge rather than keep fighting although he actually had a pretty decent chance of winning. Now, I recognize that it was an extreme situation and so I made a point not to jump any real conclusions based on it alone. But at the same time, I know I'd be loathe to ease up on knockdown any without also coming up with some sort of system to make characters pass some kind of gut check to at least not be dissuaded from moving too fast right away when they're pretty dang messed up. I'd have done it already but I'm not so sure what would be the best way to go about it-- I have a healthy fear of unintended consequences.

You forget that the established tactic for handling someone rushing with a knife is based on the attacker not dropping instantly from the shots. That's one of the reasons you're supposed to move sideways and/or behind obstacles. I believe the same as the tactical community. You believe that under that assumption, the tactical community have reached the wrong conclusion and are doing something "stupid" instead of your suggestion of a smart plan.

But you quite well displayed your ignorance on these matters when you said the preferred tactic was a double tap, which it is not. I guess you think this is a good dodge.

That you fail to reply to the physics part, I take that as silence signifying agreement. Does it change your understanding of the knockback issue that the force from the bullet is only the square root of what you thought it was?

The report Waya posted also had an interesting comparison - the physics tells us that the impact from a .45 equals that of a 10 pound weight dropped less than 1½ inches! Do you really expect that to topple anyone?

1) if the mass of the gun is incredibly huge compared to the bullet, what do you think of the mass of target compared to the bullet? Humongously huge?

2) That is impossible. In the direction of the bullet's travel the component of the forces on the gun will always be of the same magnitude as the force on the bullet.



It means "proportional to". It is generally only used when you don't know the relations and formulas, but can derive or estimate the proportions. I've never seen it used in physics, especially not in simple mechanics like this, but if someone doesn't know the formulas, I can see the benefits of using O - it effectively conceals his lack of knowledge and makes it harder to present counterarguments.

Oh yes, that's totally going to stop someone whose movement is not inhibited at all...just move sideways, and because humans run on rails the attacker won't be able to correct his course.

It's a simple bit of evolution: If your claim that the average shootout looks like a Romero movie was true, most people who tried to hold their ground against a charging attacker should be dead. Moving sideways? Pointless, the other guy would just adjust his course. Obstacles? Unless we are walking about wire obstacles, ten seconds would be plenty of time to get over one. Good old folding shovel? WOuld only be useful if you decapitate your opponents, otherwise they'll just keep hitting you and make you one of the undead, too.


I'm not going to repeat the "human body vs. rigid structures moving on rails" again, since you obviously chose to ignore that little caveat

BTW, I think the most interesting sentence from that report is this: There is no valied, scientific analysis of actual shooting results in existence, or being pursued to date.


@Banaticus:

http://en.wikipedia.org/wiki/Big_O_notation

You obviously not only have no combat training, but no concept of movement either.

Two experiments for you:

1) Try sprinting straight ahead, then try the same while moving in a tight circle, as if you were tracking someone moving sideways. You'll see you're MUCH slower when you have to turn.
2) Try catching someone on the other side of a table - you can jump on the table, and you need to slap him on the torso. Not so easy, is it?




As we've been trying to tell you, the standard tactic is not to stand your ground - evolution has happened, people are trained to move sideways or get behind obstacles, and otherwise be prepared to engage in melee. You are NOT taught that you can stop someone in their tracks by shooting them. You are the one ignoring the experiences from law enforcement.



No, we've been through that several times. You just chose to ignore those of us who from martial arts or sports know that something as weak as a bullet, or even a punch which carries 10 times the momentum, simply won't topple you, especially not on center mass. You've also said "walking is a highly complicated affair", which is complete bull - humans are very adept at walking and running.



Blows to the head can certainly knock people out reliably. Blows to the body cannot. Here you're relying on emotional fainting or other reactions to pain for immediate incapacitation (unless you manage to break their back).



You misunderstand what is said here. There is no way to determine the significance of ammunition types, hit locations, etc. It is however abundantly clear that immediate incapacitation is extremely unreliable with small arms.



Two questions I would very much still like you to answer
a) You used to think that force was O(v^2). As I have shown you, it is O(v). This is a drastic reduction, the forces involved are obviously far smaller than you originally thought - has this not changed your opinion of what happens to someone struck to a bullet
b) You think that entire tactical community, what law enforcement officers are taught, FBI training manuals, they're all wrong. What are you basing this on? That in the media discussions about new ammo for the German police, people only talked about the same 3 cases of people not stopping immediatetly when shot?

I think I'll just tell that to the next guy who's trying to tackle me even when I'm sidestepping: you can't do that, that's impossible, you have no concept of movement


And the next time somebody tells me the human brain is complicated I'll tell him that this is complete bull - every human has one and knows how to use it, that clearly proves it can't be complicated, because...well...uhm...why, actually?


I'm not the one saying their tactics are nothing but suicide because the average engagement involves the Living Dead charging without even noticing the shots fired at them...


So the answer to my question "Which part of 'Even when talking to officers' is unclear to you?" obviously is "all of it"...

I must say, this is typically you. You seem to have no ability to critically examine your beliefs. I asked you to try it, not to make a snide uninformed reply. If you did go out with a friend, stand at least 21 feet apart, and then try to see the difference between charging someone standing still and someone sidestepping, you'd clearly experience the big difference when the attacker can't build momentum.

How about the table experiment? Do you have a snide remark for that, or did you on this issue become convinced that perhaps it really is difficult to reach someone across a table?




Maybe my brain is complicated from the viewpoint of a neurologist or an AI researcher. But I, like all other humans, find in completely trivial to operate it. I don't really care about how much bio-mechanical modelling it takes to describe walking and keeping your balance, humans do it effortlessly. Walking is just not a "highly complicated" affair for humans.



Because they also mention the best examples when you talk to them? That most officers haven't reviewed all shooting incidents and only know of the most extreme cases that REALLY highlights that people don't drop?



Sigh. I know that YOU think the tactic is to just stand your ground and double tap. That is just not true. Police are not taught to double tap or stand their ground. They're taught to keep shooting, sidestep or get behind obstacles, and receive the charge.

Step 1 is you realizing that your "stand and double tap" is just that, an idea of yours. Once you have learned about the actual tactics taught, Step 2 is that you explain why people are taught to sidestep (you think this doesn't have any effect) and why people are taught to not assume their shots instantly incapacitates.

But ok, that's one question answered - you apparently still think that police tactics are based on shots immediatedly incapacitating attackers.

How about the other one? The forces involved when getting hit by a bullet is MUCH lower than you thought - doesn't this affect your opinion on how a target is affected by it? Are you really just going "well I thought it was v^2, turns out it was just v, but that doesn't really have any effect anyway"?

Sengir, so you are saying if someone is charging you that you shouldn't get out of the way? You can look on youtube for clips of the show "Cops" there are situations where the police officer is being charged and they move out of the way and keep firing. I remember a few where the officer fires his entire mag. One thing you aren't taking into consideration are misses, not every shot hits it target even at close range and especially at moving targets.

That's because they are often taught to do so. Even if it's not "officially" part of the training manual.

They are taught that if you in a situation where you must open fire on a target, do so decisively. You put him on the ground, empty your magazine into him if you have to, if he's still moving put in another mag and empty that one. If the target is so dangerous as to require bullets to stop, he's dangerous to not just you but anyone else in the area, and you need to make SURE he's down for the count, not play fancy games.

Granted, a soldier is taught differently, as they often engage multiple targets, cannot easily pull out of the situation, and thus need to conserve ammo.

But law enforcement generally can operate with the assumption that ammo conservation isn't likely to be a huge factor, and if it IS, they are probably facing an armed group, in way over their head, and need to pull back and call for backup.


-np

Huh interesting, good to know as well. I wondered why they did that didn't think their training was that different.

Not under normal circumstances. As soon as you move even slightly outside the normal paramters, things look different...just like even minor damage to the brain can have extreme consequences.


I asked around for more examples, not for the same ones. While obviously the scenario "some punk charges you with a knife" is not unknown (although still rare), the scenario "the punk turns out to be a zombie who can only be killed by decapitation" is outside of media reports...


So you obviously have not understood how a reductio ad absurdum works...

It's actually quite easy: You assume the opposite of your position is true, then draw conclusion from there and show they lead to absurdity.
So, we assume you are right and in most cases the guy running towards an officer with a knife will act like Living Dead for ~10s, uninhibited by the bullet impacts and heedless of his injuries. In that case, our hypothetical attacker would obviously have zero problems with the officer sidestepping and taking cover...he's not affected by the bullets for the time being, after all.

Now of course if we assume the attacker is already stumbling, sidestepping becomes a decent idea...

Except that in the real world, charging someone sidestepping takes considerably longer. The attacker can't just keep on building forward momentum - he has to get his feet to one side and drop his center of gravity to the other side and start pushing that way. If you move forward at an angle, you can perhaps even force him to actually slow down in order to not overshoot you. Why don't you just go out and try it with a friend? It becomes the difference between just sprinting 7 yards, and catching someone evading - do you really think this is the same? And meanwhile, the attacker is getting shot and losing blood and approaching consciousness.

Likewise with catching someone on the other side of an obstacle. It just isn't that easy to leap over a table, jump down on the side and stab someone - if you're on the other side of the table, you can easily stay out of his reach until he bleeds out - and again, meanwhile the attacker is going to keep taking fire.

And of course people are affected by bullets - they do cause pain and you can do bio-mechanical damage (nerves, muscles, tendons, bones). Maybe the guy will drop at 1 bullet, maybe at 5, maybe even 50 hits won't bring him down. There's nothing wrong with playing the chances game, and no one is saying "it doesn't have any effect to shoot someone". We're saying "you can't in any way rely on a few bullets taking your target down instantly, your tactic has to reflect that".

The guys I normally play Rugby with are still in Dessau, because THEY got to see Bolt Thrower *hrmpf*...


It is not the exception. People don't just stop because it hurts. "A few solid punches to the chest" doesn't give the target some pause. Even in something as trivial as sparring, it doesn't work - hurts like hell, and lack of oxygen becomes an issue after a while, but it doesn't prevent you from moving or throwing more punches. With the adrenaline pumping in a life-and-death situation, people will ignore even more pain.