Home Forums Hunting & Shooting Ask The Gunwriters Killing versus stopping

Excellent points, gentlemen. It's apparent you both paid attention in physics class. Jordan, it's also apparent you paid attention in Psychology class as well.

THANK YOU Jordan.

I am NO mathematician. I didn't have Roy Rogers math < trigger nomitry> G.>>>>SO I can't discuss it in mathematical terms.

HOWEVER your post is the BEST description to convey the concept I have relative to 'bullets & terminal performance'..

The TRANSFER of E and Momentum is what I see in my mind.

Thanks Again

Jerry

Taken out of context that is a poorly worded sentence. But For some reason unknown to me momentum was not taught at the class I attended we skipped the whole chapter. I have often thought because we were a class not required to have calculus training.

As for the DVM deal I don't know what to say other than perhaps this is a good time to try ignore.

An interesting subject. Thank you gentlemen.

[img]http://Elastic and Inelastic Collisions. A perfectly elastic collision is defined as one in which there is no loss of kinetic energy in the collision. ... Momentum is conserved in inelastic collisions, but one cannot track the kinetic energy through the collision since some of it is converted to other forms of energy.[/img]

This is shared HINT HINT I did not write it.

Is all kinetic energy lost?

Why does the above definition use the words " some Kinetic energy is lost" not all?

Where does it go?

Is there a way to predict how much is converted, and how much is conserved?

If it gets converted to what?

How does one differentiate the type of collision? As in total ,partial, and non elastic.

How does one define " momentum"?

If I missed or not dispatch the bull then he runs me over iis that collision elastic, inelastic or partially elastic?

The next post is a shared video of the skulls .?

Thank you.

For a man that claims to have enough education to be a DVM, you only post "Google fu" with BS commentary, sounds a bit fishy.

Is being hyper sensitive to using terminology that in fact is mostly likely true give one Carte Blanche to become troll like?

Is using bowling balls and arrows for Ballistic analogy proper, where as using Ballistic behavior of a sabot kinetic roundout of a 105 mm rifled barrel unacceptable?

Is formulating equations based on blasting kidney stones out of humans, a direcect correlation to center fire rifle shots into a ruminant?

Is it good to have frangebile properties in a bullet in one post for Terminal effects, but "bad physics if some one else posts it?

Is there not several documented cases of bullets, and or other objects in the brain or CNS system and not cause instant death, in fact some will survive? Why perhaps does this occur?

Could it be lack of. Oh. No. Not Energy again?

I'll play.

- Energy is never "lost", per se, but it can be transferred outside of the system in question, or converted to other forms. In the case of an inelastic collision, some of the kinetic energy in the system in consideration is converted to other forms of energy, the amount of which depends on the nature of the collision

- Some kinetic energy is transferred from one object to another, and some is used to perform other actions

- Due to the individualities of every shot, there's no way to predict how much KE is conserved in the collision, with any accuracy- part of the reason that using "FPE" as a killing-power guideline is folly

- The KE that is not conserved in the collision get converted into thermal energy, is used to deform the bullet, deform tissue, etc

- Perfectly elastic collision is when objects collide without deformation and bounce off of each other (billiard balls colliding), an imperfect inelastic collision involves deformation of the objects, and the objects bounce off of each other (car accident), and a perfectly inelastic collision involves deformation of the objects and the objects stick together after colliding (bullet colliding with an animal)

- A working definition could be the tendency of an object in motion to stay in motion

- Imperfectly inelastic



What's your point? The fact remains that using the kinetic energy of a bullet as a primary means to quantify its killing effectiveness, is extremely ineffective.

The dude claims to be DVM, which means enough education to not be asking such mundane questions.

When all discussion is winnowed out,Phil said it best.Note he left out the word if.

I agree. Utterly. Old men who have 'been there and been doing that' for many decades have a way of capturing profound wisdom in few words.

His patients all think he's brilliant.

Agreed. On the topic of the OP, that's about all that needs to be said.

I think that is a bit unfair. There's any number of highly educated people who have no grounding in mechanics, and no real need to know it. FWIW my sister is a vet, and teaches it at university. Her husband is a professor in veterinary medicine, specialising in equine virology. I doubt they'd ever have any need to consider the difference between elastic and inelastic collisions, and I doubt they've even thought about anything to do with them since high school.

Unfortunately for those of us with an engineering background or interest in physics, there are many people who really have very little knowledge of this stuff, nor any practical reason to know it.



There's a range of ways the kinetic energy is "lost". Energy is used to do work, pushing bits of animal out of the way of the bullet, tearing through skin, muscle and organs and breaking bones (or, at a finer scale, breaking molecular bonds). Some gets turned into sound and some into heat. It doesn't really matter much in a practical sense though, because ultimately what kills the animal is damage to structures vital to sustaining life, and that depends on a number of factors. Crudely, a bullet whose path transects something important, and which has the construction and momentum to drive through and cause enough damage along the way.

Thanks Dan, THAT has been my contention all along. NOT that it's 'kinetic' E but Energy of some description.

And with Jordan's post earlier
---------------------------------
"This is correct regarding collisions, but it is important to note that although kinetic energy is not conserved in inelastic collisions, there is still an energy transfer from one object to another. In fact, an object can only have measurable momentum if it also has kinetic energy. When you mentioned that a wound channel is produced by direct applied force, this is indirectly saying that there is an energy transfer, since change in kinetic energy is equal to the force applied, integrated over the displacement of the tissue. Likewise, the change in momentum of the tissue is equal to the force applied, integrated over the time of interaction.

So there is no question that when a bullet strikes, there is a transfer of momentum, kinetic energy, and that there is a force applied which is responsible for these changes in the tissue. I think the reason that so many of us have become hyper-sensitive to the mere mention of the word "energy", is because of all the focus and emphasis that for decades was placed on energy as a metric of killing effectiveness, using distorted mechanisms and quantified thresholds. People used kinetic energy all wrong in trying to determine killing power, and now we can't stand when somebody brings it up. Kind of like our reaction to an over-played song coming on the radio (even if we liked the song when it was originally released)."
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You TWO guys have satisfied my inquiry/curiosity/confusion.

I repeat what I've said repeatedly since joining the 'fire' in 2010...

No work gets done with out Energy.

Thanks Again

Jerry

edit to Correct My puter. It placed something ELSEWHERE than where I put it.

First of all Thank you Dan_oz. I am gobsmacked by your support. Truly.

Let me try my latest postulate.


If energy is in fact measured in the definition of momentum, plus if in fact any definition of collision all energy is not lost just simply not fully conserved.

And the loss of such energy is not predictable.


And if the energy is lost it happens inside the wound channel.

And if losing energy inside a wound channel is beneficial to achieve the desired effect

To not use energy prior to the arrival of the projectile to the wound channel as a way to compare or quantitate " dosage" of effectiveness or performance in a cartridge used to harvest game seemslike a good thing to consider ( 2 achieve the desired effect)



Kinda like do I give the cow 30 cc of oxytetracyline 300 mg per ml. Or 60 cc? ( an antibiotic for bacterial infection) this antibiotics effectiveness is bacteria stactic and dosage dependent. Now of course I should consider the mass of the animal to determine how much I should administer. I want to have it work and stop the bacterial infection. But I don't want to compromise the event by overdosage.

Now wether or not I go I.V. Or P.O. Or I.M. ( intravenous, per oral, or Intramuscular) or the carrier base etc, etc.will also be very crucial to treatment success, but certainley the amount of the antibiotic administered will also make or break the deal.

Just my observation.

But please show where in this individual post of 13 pages I personally said much about energy being paramount. Or " The Single Thing". If I did in fact say those things I am in error and apologize.

But I certainley consider energy in cup and core bullet " dosages".

I think velocity may be more important to consider in monolithic "treatment"

There was a wonderful Terminal Ballistic test run here on the campfire some years back. I was amazed at how well the 130 grain 30 caliber Barnes fared. It was shooting bovine leg bone point blank, then measuring wet paper penetration. Really well written study IMO.

A chain is only as strong as its weakest link. Therefore shot placement, attitude of animal, yardage, environment, weather, most of these things we cannot control.....only adapt to and consider at the time of the harvest event .....but we can select the accuracy, bore weight, sectional density and Ballistic Coefficient etc,etc.,and or lack thereof, and energy potiential of the cartridge prior to the harvest event.

All these things I am going to reccomend levels on based on harvest event scenario ,and all of these parameters I feel are worth considering. So I will continue to consider.

I also feel I should limit my thoughts and suggestions to standard yardages. I E under 500 yards in the future.

Just something 2 ponder.

Angus, remember !!

Some don't like or don't believe E is relative......

I've heard (read) "FPE doesn't matter", more than once.

IMO some will NOT admit/agree that E plays much IF any role of importance in bullets'
terminal performance.

Good Luck

Thnx FOR this thread (discussion)

Jerry

I do not like canned peas ............ should I become a troll if some one says they like them or eats them?

Just like I have a license to practice medicine.....they call it practice for a reason......it ain't rocket science.

Most of us here have a license to hunt, we can all learn from each other endevours expierences and practice ...if we just listen to each other and be considerate and open.

It all boils down to

" What is your intent?"