Stopping Power- A Martial Artist Perpective.

[JohnKSa]

No bullet cuts anything. The permanent cavity is created by exceeding the leastic limits of the tissue and it tears.
Knives cut. Bullets tear.

Knives are pressure amplifiers. They take a modest amount pressure applied to the handle (PSI = pounds per square inch) and deliver the same amount of force over a much smaller area (the edge of the blade). That produces more pressure. The pounds stay the same but the number of square inches of area is much reduced resulting in a higher value of PSI. The sharper the knife the smaller the area of the knife edge and the higher the pressure.

Example--3 pounds of force applied to about 2 square inches of handle = 1.5PSI. 3 pounds of force applied to about .001 square inches = 3,000psi.

This very high pressure easily exceeds the elastic limits of the tissue contacted by the knife edge and it tears--but on a very small scale at the contact point of the blade edge.

Bullets don't need to amplify pressure since they already have a huge amount available. They tear the tissue they contact due to the application of high pressure. They do exactly the same thing as a knife but also have enough impact energy to create blunt trauma (the stretch cavity) as well.

If you could swing a knife as fast as a bullet travels, the result would be very similar in that you would get a temporary stretch cavity as well as a cutting type injury.

 

[mpmarty]

Well, I'd be perfectly happy to rely on my martial arts experience. Only one small problem. In the DOJO, we all knew that if we started to overpower an adversary the adversary wouldn't pull a gun, his buddy wouldn't pull a gun and so on and so forth.. On the street a cop would have to be a fool to rely on any type of martial art in a confrontation with a bad guy. Yeah, breaking up a bar fight might be one but I doubt it. Personally, I carry a 10MM with Winchester silvertips at over 600 ft lbs of energy that expand to over .75" and penetrate well. I have only had to fire in self defense once in my life, I hope I never have to again but when I did, I put two center of mass and he slowed down enough for me to give him a third eye. Fight ended quickly. I believe in head shots.

 

[brickeyee]

"This very high pressure easily exceeds the elastic limits of the tissue contacted by the knife edge and it tears--but on a very small scale at the contact point of the blade edge."

I will remember your 'theory' the next time I use a sharp edge to cut microscope sections.
Tearing does not occur unless my microtome is dull. Even at the highest magnification.

 

[JohnKSa]

brickeyee,

What is cutting then?

 

[Geronimo45]

"If you could swing a knife as fast as a bullet travels, the result would be very similar in that you would get a temporary stretch cavity as well as a cutting type injury"
If you could swing a knife that fast, you're liable to cut somebody in two.

 

[jon_in_wv]

I'm gonna start carrying a sword. Cut a dude in half, one shot stop.

I wonder if I only cut him 10 inches deep if that would be "dangerous underpenetration"?? Just kidding....


I've gotten a LOT of responses to this thread. I'm glad to see so many of you have given this a lot of thought.

 

[brickeyee]

Cutting is not tearing, even at the microscopic level.
When you cut with a sharp edge you produce a clean separation.
Tearing produces a ragged edge since the material is not cleanly severed.

I can tell if my edge gets the slightest bit dull when preparing specimens.
You can feel the drag when you cut, and then instantly see the ragged cut under the microscope.
It is possible to section individual cells and get a clean cut that allows the viewing of the cell contents in clear cross section.

 

[jon_in_wv]

Thank you BIll Nye the Science Guy! This is actually pretty good, we went three pages before we wondered off into guns vs. knives. Actually it is useful though. From what I have read about knife attacks (and witnessing them) and knife murders it generally takes multiple, perhaps 15-20, knife wounds to cause sufficient blood loss to cause incapacitation (can of worms opening sound added here) While blood loss is oftenly heralded when it comes to gunshot effectiveness, the fact of the matter is that most knife wounds bleed much more profusely, and unless they severe a major arterie that causes SEVERE blood loss to the heart or brain it just isn't that effective as a stopper. It will stop them eventually, yes, but the "one shot stop" effect isn't there. I have seen victims leaving trails and pools of blood, with knife wounds that were literally standing open themselves to expose flesh and they continued to fight or run. NOT isolated cases, but rather often. In the military they taught multiple stab wounds to specific areas to ensure effectiveness and we are talking about with a large bayonet or K-Bar to the neck or heart.

 

[Soybomb]

I'd like to point out too fwiw that the article you linked to cites the work of people like Martin Fackler. Dr. fackler isn't just a paper writer but a retired battlefield surgeon. The man has seen a few bullet wounds in his days.

You'll certainly understand my skepticism when someone like dr fackler says that bleeding is one of the primary means of incapicatations and you say it must be wrong.

 

[JohnKSa]

Cutting is not tearing, even at the microscopic level.
When you cut with a sharp edge you produce a clean separation.
Tearing produces a ragged edge since the material is not cleanly severed.

That's not really an explanation.

I say that cutting is very precise tearing achieved by amplifying and precisely focusing pressure--the sharper the edge, the more precisely the tear follows the path of the edge and the harder it is to see the evidence of tearing.

I think what you're saying backs that up--as the knife dulls, the tearing becomes more and more visible. This certainly holds true at the visible scale.

Soybomb,

Bleeding is a primary means of incapacitation. But not even Dr. Fackler claims it's a fast means. IMO, having your attacker bleed to the point of incapacitation is the second worse scenario possible. The absolute worst case is that they're not incapacitated at all.

All but the most rapid blood loss scenarios will give an attacker plenty of time to do you a lot of damage before incapacitation occurs.

jon in wv,

It's not about guns and knives, it's about the different types of trauma. I'm agreeing with you that the trauma from a punch is very similar to one type of trauma from a bullet (temporary stretch cavity) and pointing out that the other type of trauma from a bullet (permanent wound cavity) is similar to the trauma from a cut. While things may not be quite as rigidly on topic as some would like, the discussion has not digressed far from your original points.

 

[jon_in_wv]

Don't get me wrong. That statement was made with a grain of salt (humor). I am more than happy with the direction and the quality of the discussion I seem to have sparked here. I'm certainly not implying that people have to "ridgidly" adhere to my topic. Loosen your tie a bit professor.

 

[Phil DeGraves]

There is no such thing as "Stopping Power" with a handgun. Under 2600fps or so, Kinetic energy, etc. means zilch. The only thing that counts is where the bullet hits and what tissue gets destroyed.

 

[jon_in_wv]

Sgt. York took out 7 German soldiers with seven shots from his 1911 during his famous charge in WW2. I'm sure he might differ with you. I'm sure that was just seven flukes though.

 

[AsianDragonPower]

whats the best handgun for ammo plus stopping power

 

[AStone]

whats the best handgun for ammo plus stopping power

Oh, I don't think any one on this forum has any opinion about that.

 

[jon_in_wv]

The one that fits your hand and you shoot it well. Hitting your target is more important than the actual ammunition used. Some guns don't fit some people, some people don't like some calibers.