Home | Ezine | Forums | Links | Contact
NitroExpress.com: John Pondoro Taylor' KO effect VS SD x Velocity

View recent messages : 24 hours | 48 hours | 7 days | 14 days | 30 days | 60 days | More Smilies


*** Enjoy NitroExpress.com? Participate and join in. ***

Hunting >> Hunting in Africa & hunting dangerous game

Pages: 1 | 2 | (show all)
DarylS
.700 member


Reged: 10/08/05
Posts: 27003
Loc: Beautiful British Columbia, Ca...
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: Tatume]
      #116334 - 06/10/08 05:16 AM

I tend to agree with Elmer's theories and they indeed show results in the field, except he left out bullet diameter - a very big player in killing, stopping when using body shots.
Unlike some, I prefer an exit hole.

--------------------
Daryl


"a gun without hammers is like a Spaniel without ears" King George V


Post Extras: Print Post   Remind Me!   Notify Moderator  
hoppdoc
.400 member


Reged: 02/03/06
Posts: 1791
Loc: Southeastern USA
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: DarylS]
      #116337 - 06/10/08 06:01 AM

Specifics on "stopping cartridges"??

You could set up a sequence of increasing cartridge "stoppers" if you have one agreed upon reference. The reference would obviously have to include the object shot as well for constancy-

For example--if the 458 Wm solid at 2150 was good for Ele the a safe assumption would be cartridges of similar bullet type/velocity attaining the same agreed depth of penetration but larger diameter should be "better" stoppers.

A better stopper would also be one attaining a deeper depth to a point of complete penetration of the animal as compared to the agreed upon standard. How to compare against larger bore, similar penetration?? I dunno--

Fun to think about anyway--

--------------------
An armed man is a citizen of his country, an unarmed man just a subject.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Ripp
.577 member


Reged: 19/02/07
Posts: 16072
Loc: Montana, USA
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: 9.3x57]
      #116349 - 06/10/08 09:54 AM


All this talk about energy is irrelevant unless bullet construction is somehow factored into a mathematical formula, a requirement that none of the formulas {except Taylor, but only sort-of as JPK identifies}.

In the final analysis, field shooting is the only way to KNOW how a load will perform, and even that requires a fairly large number of shots-on-game in order to form the basis of semi-accurate predictions if an unknown {like a different species of game, radically different shot angle, etc} is injected into the discussion.





++++++++++++++++



Agree totally with the above---shooting the game you are loading for IS IMHO, the only sure way,,one can guess, predict, calculate, etc the outcome and be fairly close,, especially with all the info at our fingertips..all we have to do is google and find more info in an hour than we could have spending a month at the library a decade ago..

Bullet construction must be factored in.. perfect example I experienced was using Nosler Accubonds faster than their construction would hold up to..which, in my experience they are a good bullet up to 3000fps or slightly more but after that..all bets are off...however A-Frames or Barnes of identical weight and velocity hold up to 3100 and above with no problem..at least that has been my experience on game ranging in size from pronghorn, impala, deer, elk, eland and kudu..

Not sure there is a sure fire formula, Keiths included..but Taylor is definitely not as well...

As mentioned..makes for very interesting debates around the campfire with beer in hand...

Ripp

--------------------
ALL MEN DIE, BUT FEW MEN TRULY LIVE..


Post Extras: Print Post   Remind Me!   Notify Moderator  
hoppdoc
.400 member


Reged: 02/03/06
Posts: 1791
Loc: Southeastern USA
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: Ripp]
      #116355 - 06/10/08 11:03 AM

The use of solids should be predictable due to the constancy of bullet shape, type work done, and how a standardized target would handle the "negative work" of stopping the bullet vs some reference.

Once you switch to a bullet that changes shape with impact causing different dynamic diameter of bullets you are back to empiric results again--way too many variables operating on the target.Methinks reasonable Guessing and experience would rule.

--------------------
An armed man is a citizen of his country, an unarmed man just a subject.


Post Extras: Print Post   Remind Me!   Notify Moderator  
DarylS
.700 member


Reged: 10/08/05
Posts: 27003
Loc: Beautiful British Columbia, Ca...
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: Ripp]
      #116356 - 06/10/08 11:06 AM

Pull up a stump, Ripp, Hoddoc and Rod. You guys are spot-on!
: It's a mite cold around the camp fire these nights - maybe a bottle of Appleton's Estate?

--------------------
Daryl


"a gun without hammers is like a Spaniel without ears" King George V


Post Extras: Print Post   Remind Me!   Notify Moderator  
ALAN_MCKENZIE
.400 member


Reged: 24/03/04
Posts: 1214
Loc: Western Australia
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: DarylS]
      #116368 - 06/10/08 01:28 PM

Ditto,Daryl,Ripp,Hoppdoc & Rod.

Al

--------------------
"Dogs always bark at their master"
Sir Seretse Khama.25th June 1949


Post Extras: Print Post   Remind Me!   Notify Moderator  
JPK
.375 member


Reged: 31/08/04
Posts: 734
Loc: Chevy Chase, MD
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: ALAN_MCKENZIE]
      #116375 - 06/10/08 02:09 PM

A couple of thoughts.

1. Stopping Power when used by Taylor, etc, in the discussion of big bore rifles = stopping a charging elephant with a solid bullet, even when the shot misses the brain. But there are other uses of "stopping power", for example handguns and body shots. So defining Stopping Power, as mentioned, is critical.

2. Solid bullets have varying shapes which produce different results. The most reliable in the scope of Taylor and elephants, etc, until relatively recently, was the hemispherical round nose. Today we know its the truncated cone flat nose, with a wide meplat. Worst was the old style 470 bullet with a progressive ogive and pointier shape than the hemisherical round nose, too often veering off course.

3. Energy has a direct correlation with penetration when discussing solid bullets. For example, if two of the same bullets are fired, one at greater velocity, and so with greater energy, the one that is faster and has more energy will penetrate further.

4. Energy has a more or less direct correlation with stopping power, stopping power defined as stopping a charging elephant. But momentum is the better measure since bullet weight is more significant than velocity, given that velocity is "sufficient."

5. Limiting the discussion to solid bullets and elephants, it's really remarkable that the Brits got it very right about 110 years ago when they defined the parameters of successful cartridges for braining elephants to be SD +/- .305, V +/- 2150fps.

6. Hopdoc is right, a table of cartridges of ascending stopping power, as defined by stopping a charging elephant, can be easily put together. Taylor has already done it. His table, when corrected for errors and for real, in the field velocity, and updated with newer cartidges is pretty good. Ignore the "knock out" predictions and substitute "knock down" or "turn a charge" and his table is very predictive, according to over a century of real experiences.

But when you move into more variable areas, like softs and body shots, there is going to be some SWAGing going on. Taking a whitetail deer as an example, a pretty poor bullet is actually more likely to "stop" a deer with a DRT than a good bullet that will produce a dead deer more reliably, but with less drama. Take a Ballistic Tip and a Partition for examples.

Hopdoc, take a look at Taylor's KO index and his tables of cartridges and you've got a pretty good heiarchy for stopping elephants.

JPK


Post Extras: Print Post   Remind Me!   Notify Moderator  
shakari
.400 member


Reged: 09/02/03
Posts: 1107
Loc: South Africa
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: JPK]
      #116386 - 06/10/08 11:17 PM

As JPK says, the Taylor KO index was solely supposed to refer to head shots on Elephant and from my experience it's pretty accurate for that.

I find it astounding to think he worked the whole thing out from scratch using only paper, pencil and a typewriter. He ust have been (to coin a phrase from a Ian Dury) 'a clever bastard'.

--------------------
Steve "Shakari" Robinson
Kuduland Safaris (Africa) Ltd
info@kuduland.com
www.kuduland.com



Post Extras: Print Post   Remind Me!   Notify Moderator  
DarylS
.700 member


Reged: 10/08/05
Posts: 27003
Loc: Beautiful British Columbia, Ca...
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: shakari]
      #116390 - 07/10/08 01:02 AM

As far as the bullet itself possessing some form of engery to dump into the animal, I disagree.
This bullet, this vessel, has momentum based upon velocity and speed and therefore poessesses some abiltiy to penetrate and in the high speed expanding type, disrupts the tissues in relation to it's diameter and violence of expansion. The greater the speed upon impact and the wider the expansion, the more tissue is disrupted - by the expanding bullet - there is no energy thrown into the tissues from the bullet - but BY the bullet. Any disruption of tissue is a 'result' of the speed and the bullet's expansion - not caused by some mystical bust of energy from the bullet itself as is commonly thought or imagined. Of course, the higher the speed, the higher will be this wierd number called foot pounds of energy - but - it has no co-relation to what is actually caused in damage.
What I am holding to is there is no relationship between damage or the ability to do damage and the actual number of the foot pounds of energy. The number itself is meaningless - the 22/250 possesses more fpe than a .45/70, yet the .45/70 is a buffalo ctg., long range match round and the little .22 isn't, yet the numbers, these fpe many people seem to think are meaningful have no integrity - they are actually meaningless in game shooting. A better formula is necessary, but then, in game shooting, if one has done enough of it, animals can't read ballistic papers and therefore don't know how to react.

--------------------
Daryl


"a gun without hammers is like a Spaniel without ears" King George V


Post Extras: Print Post   Remind Me!   Notify Moderator  
shakari
.400 member


Reged: 09/02/03
Posts: 1107
Loc: South Africa
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: DarylS]
      #116393 - 07/10/08 01:41 AM

Daryl,

I don't understand who you disagree with? - My point was that the Taylor KOV was only supposed to have real relevance when applied to head shots on Elephants - and although I didn't mention it, I should also have said only with solids.

My point is that (as far for as I know), no-one else except Taylor has tried to work out a scale for the same purpose as the Taylor KOV was for........ therefore comparing it to anything else is comparing apples to oranges.

--------------------
Steve "Shakari" Robinson
Kuduland Safaris (Africa) Ltd
info@kuduland.com
www.kuduland.com



Post Extras: Print Post   Remind Me!   Notify Moderator  
Tatume
.400 member


Reged: 09/06/07
Posts: 1091
Loc: Gloucester, Va USA
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: DarylS]
      #116397 - 07/10/08 02:51 AM

Quote:

As far as the bullet itself possessing some form of engery to dump into the animal, I disagree.




You're right again, Daryl. For the purpose of comparing game cartridges, energy is hype, the purpose of which is to sell new, faster cartridges. It gives the ammo companies and the gun writers an excuse to square velocity, and make big differences out of little differences.


Post Extras: Print Post   Remind Me!   Notify Moderator  
JabaliHunter
.400 member


Reged: 16/05/07
Posts: 1958
Loc: England
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: DarylS]
      #116411 - 07/10/08 05:56 AM

Quote:

there is no relationship between damage or the ability to do damage and the actual number of the foot pounds of energy.



Just look at hunting bows...


Post Extras: Print Post   Remind Me!   Notify Moderator  
JPK
.375 member


Reged: 31/08/04
Posts: 734
Loc: Chevy Chase, MD
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: JabaliHunter]
      #116416 - 07/10/08 11:52 AM

Quote:

Quote:

there is no relationship between damage or the ability to do damage and the actual number of the foot pounds of energy.



Just look at hunting bows...




You all continue to confuse the absolute realtionship and 100% correlation between energy and penetration when discussing solid bullets and everything else.

Recall, two identicle bullets fired at two velocities; the faster will penetrate deeper. (and so cause greater damage as well, by means of a longer - and likely wider too - wound channel)

Discussing Taylor's tables, he uses momentum rather than energy to come up with his KO values. Momentum relies on velocity rather than velocity squared and so emphasises bullet weight in his formula, which it ought to. But use his formula and two identical bullets at two different speeds and - guess what? - you will come up with two different KO values, the greater of which reflects the greater velocity.

Velocity is a critical element of the mathematical calculation of energy. Ignoring velocity, and so energy, is ignoring a huge factor in penetration and capability of any solid bullet. Leads to dumb ass arguements along the lines of 45-70 = 458wm = 458 Lott = 460Wby. Nothing could be farther from the truth. But for best results, follow the Brit lead of 110 years ago and forego "too much" velocity for bullet weight and keep near the SD = +.305, MV = ~2150fps and move up in bullet diameter, weight and stopping power for given recoil rather than more penetration than is required.

JPK


Post Extras: Print Post   Remind Me!   Notify Moderator  
JPK
.375 member


Reged: 31/08/04
Posts: 734
Loc: Chevy Chase, MD
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: JPK]
      #116417 - 07/10/08 12:05 PM

"As far as the bullet itself possessing some form of engery to dump into the animal, I disagree.
This bullet, this vessel, has momentum based upon velocity and speed and therefore poessesses some abiltiy to penetrate and in the high speed expanding type, disrupts the tissues in relation to it's diameter and violence of expansion."

Momentum is a component of energy or potential work.

Momentum is a calculation based on velocity and bullet weight.

Energy is also, though since velocity is squared in the energy calculation energy favors velocity over bullet weight.

Both are measures of potential work.

So a bullet has its own energy, or potential for work, anytime it is moving. Same thing with momentum. They are two different measures of the potential for work with one emphasizing weight (or at least not de-emphacizing it) and the other velocity.

So a moving bullet has it own independent energy to dump into an animal; it also has it own independent momentum to transfer... Two sides of a coin.

JPK


Post Extras: Print Post   Remind Me!   Notify Moderator  
Sarg
.400 member


Reged: 20/01/07
Posts: 1365
Loc: Nil
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: JPK]
      #116419 - 07/10/08 12:44 PM

Is there any formula that takes in rotational force ? this seems like free energy as the spin keeps going as velocity drops off !

Post Extras: Print Post   Remind Me!   Notify Moderator  
9.3x57
.450 member


Reged: 22/04/07
Posts: 5521
Loc: United States
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: Sarg]
      #116421 - 07/10/08 12:54 PM

Quote:

Is there any formula that takes in rotational force ? this seems like free energy as the spin keeps going as velocity drops off !




Sarg:

Sciuchetti's impressive testing documented in HANDLOADER No.193/June-July 1998 pretty much closes the door on rotational force as having any noticeable effect on terminal ballistics.

By the way, if you want to see the effects of kinetic energy just watch the progression of effects on bullets as velocity increases on his chart.

JPK's expounding is pretty much on target as with NON-deforming bullets, speed makes the projectile penetrate farther, ditto FMJ handgun rounds.

It is interesting to read all this. JPK is interested in FMJ's on elephants. I have no experience on elephants but I do have some experience with FMJ's in pistols on butcher stock {some dozens}. It is interesting that slower FMJ's produce less trauma than do faster FMJ's. And faster FMJ's, even of smaller caliber, sometimes produce more trauma surrounding the bullet hole/path than do larger bullets. Interesting. Regardless, at typical service pistol speeds, all pistol FMJ's lack decisive "stopping power", whatever that is, unless CNS is hit and then they all look pretty good.

A .243 at such and such ft-lbs energy kills elk less well than does a .340 Wby at higher ft-lbs. In this case, ft-lbs is a "good" indicator of killing power.

Ft-lb's fails many times in other examples.

All this chat does is highlight that NO mathematical formula is a perfect predictor of killing power. Some are better indicators under certain circumstances, but fail under others.

Best to shoot game. Second best to compare in a testing medium/media.

--------------------
What are the Rosary, the Cross or the Crucifix other than tools to help maintain the fortress of our faith in Jesus Christ, the Son of God?


Post Extras: Print Post   Remind Me!   Notify Moderator  
hoppdoc
.400 member


Reged: 02/03/06
Posts: 1791
Loc: Southeastern USA
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: JPK]
      #116430 - 07/10/08 03:59 PM

The positive work a bullet does in penetrating an animal is manifested in the distance the bullet travels through the animal. The work done is described in terms of ENERGY. More work means more energy expended.

The work done is a measurement of force thru a distance, with force associated with the change of momentum(mass x velocity)occuring.

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


What type of work the bullet does is related to the bullet characteristics. Large "solid" FMJ bullets of similar energy penetrate less than identical smaller diameter bullets of the same energy working against similar resistance. Thus some "types" of bullet work are better than others at accomplishing the desired result. Give me the one than penetrates enough with the largest diameter at a given energy level, please.

The animal performs negative work in stopping the bullet.Tougher game implies more resistance to the bullets required. Soft points work great on whitetails but not on Ele. If the animal'negative work cannot equal the positive work of the bullet, the bullet penetrates the animal and the negative work is finished in the gound or elsewhere.

What concerns us is how the work is performed satisfactorily by a certain bullet at a certain velocity.Which bullet/velocity combo is best??

Thank goodness empiric observation and deduction do quite well without a physics approach. Fun to consider though!!

--------------------
An armed man is a citizen of his country, an unarmed man just a subject.


Post Extras: Print Post   Remind Me!   Notify Moderator  
9.3x57
.450 member


Reged: 22/04/07
Posts: 5521
Loc: United States
Re: John Pondoro Taylor' KO effect VS SD x Velocity [Re: hoppdoc]
      #116452 - 08/10/08 01:34 AM

Maybe the most significant example of velocity and bullet shape influencing bullet terminal performance was with the revolutionary {for its time} change that occured in military bullets from the long heavy RN FMJ's to the pointed spitzers of the 1900-1910 era.

Hydrostatic affect and "explosive" wounds of the new bullets/loads are well documented in military literature, both on the battlefield and in test animals. Increasing velocity by around 500 fps or so dramatically changed the scene, along with the change in shape of the FMJ bullets. Bullet shape also infuenced this, in that spitzers upon striking flesh do not maintain direction consistently and yaw in the target caused catastrophic wounds that were not noted with the previous RNFMJ's. This is easily demonstrated in my test media, also. Previous heavy RN's were known as some of the least lethal military bullets ever made, unless impact occured at very close range where hydrostatic effect was magnified by high velocity. During the Boer War and Span-Amer War, wounds caused by the common highly stable RNFMJ bullets in excess of about 500+ or so yards were noted {with some implied surprise} by military medical personnel to be through and through without peripheral trauma {hoppdoc can give you the medical terminology}. Such wounds at similar ranges caused by the later spitzer FMJ's were noted as far more severe, as the ballistic properties of the bullets {higher initial velocity and pointed, more aerodynamic shape} allowed supersonic speeds to be carried out much further than that of the previous RNFMJ's.

Difference?

Velocity and bullet shape, obviously .

This example particularly demonstrates JPK's point of bullet shape and what can happen if bullet shape varies. All "FMJ's" are not created equal. Some military literature notes increase in kinetic energy as the deciding factor in increasing terminal performance of these bullets which could be said to be true as long as bullet shape is noted. But even merely increasing start speed will carry explosive wounding effect further afield even with the same bullets.

"Kinetic Energy" is not a perfect formula by any means, but it cannot be said to be "wrong" in every case. And, depending on the "case", it can be a very poor predictor of comparative "killing power".

--------------------
What are the Rosary, the Cross or the Crucifix other than tools to help maintain the fortress of our faith in Jesus Christ, the Son of God?

Edited by 9ThreeXFifty7 (08/10/08 02:41 AM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | (show all)



Extra information
0 registered and 95 anonymous users are browsing this forum.

Moderator:   

Print Topic

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled

Rating:
Topic views: 7891

Rate this topic

Jump to

Contact Us NitroExpress.com

Powered by UBB.threads™ 6.5.5


Home | Ezine | Forums | Links | Contact


Copyright 2003 to 2011 - all rights reserved