This post contains information that is helpful to me, but I intend to stick with a 230 grain bullet at standard pressures, since the Detonics is designed for that type of load.Originally Posted by Ghost Dog
This post contains information that is helpful to me, but I intend to stick with a 230 grain bullet at standard pressures, since the Detonics is designed for that type of load.
I really appreciate the 2 links, especially the 2nd one from 2015 ! ! !
That specific information is very helpful, thank you ! ! !
You're welcome. Hopefully, I can help you get ''out of the weeds'' regarding the ΔE15/EKE parameter and what it means. There's a lot that you're attributing to the parameter that shouldn't be.
ΔE15 (or EKE) has nothing to do with a cartridge's muzzle signature (flash or blast), the action of propellant gases vented from the muzzle, or any psychological response of the subject struck by a projectile. The only thing that ΔE[SUB]15 quantifies is the amount of kinetic energy that is lost by a projectile during its passage through soft tissue or ordnance gelatin from a depth of one centimeter to a depth of 15 centimeters. The amount of kinetic energy lost is expressed as a negative value (loss) in either joules or foot-pounds and must be determined either through the use of a physical model (that is, high frame rate video analysis of a bullet passing through ordnance gelatin) or by computation using any one of the five existing mathematical bullet penetration equations in conjunction with a water test (when necessary to induce projectile expansion).
Once ΔE15 has been determined, the value must then be applied to any of the three provisional incapacitation equations along with the appropriate coefficients (for 'a', 'b', and 'n') in order to calculate the probability of incapacitation or P[I].
1.) P[I] = [1 + e -(-a + b(logΔE15))]-1 (Dziemian, 1961)
2.) P[I] = 1 – e -a(mv₀¹·⁵ - b)ⁿ (Sperrazza & Kokinakis, 1965)
3.) P[I] = 1 – e -a(ΔE15)ⁿ (Sturdivan & Bruchey, 1968)
Configuration factors are constant for expanded JHPs (regardless of diameter), FMJRNs, FMJFNs, WCs, SWCs, etc. They can be found in the literature cited for all of the mathematical models that I mentioned earlier. On the other hand, ΔE15 values are dependent upon the diameter, mass, impact velocity, drag coefficient of the specific test projectile as well as the density of the target medium and they vary accordingly with each individual test. Since ΔE15 is a value that is unique to each specific test, there is no ''one size fits all'' ΔE15 for any one given bullet mass, diameter, or configuration.
In this thread, there are examples of standard pressure and +P loads in the calibers that you mention. Even amongst those few, ΔE15 values must be determined independently of one another and must, once again, be obtained using the rearranged mathematical bullet penetration equation of your choice. As far as your statement, ''And I believe physiological relates to psychological but would like very much to get some numbers from you''...there is no number that that I can provide to you that could ever quantify such a relationship if it existed in the first place.
If there is a specific ΔE15 value that you would like for me to provide you with, I can do so via PM if you can provide the variables needed—I can help with that,too.
In the case of water testing, since liquids (water) cannot support a shear force whereas solids (e.g.: 10% ordnance gelatin or soft tissue) can, the penetration depth of a projectile in water must be ''converted'' to its equivalent depth of penetration in 10% ordnance gelatin or soft tissue through the use of a mathematical bullet penetration model. All of the five bullet penetration models are capable of doing so with high correlation to actual gelatin test data and excellent accuracy. The only values that are needed to use these equations are the bullet's drag coefficient, density of the test/target medium, post-impact diameter, post impact mass, and its velocity at impact. I advise against the use of plastic beverage containers in testing because the polymers used in their construction introduce strength effects into the experiment that can skew test results significantly. The best options for testing in water are sealable polyethylene 1-gallon freezer/storage bags or the ½-gallon paperboard cartons used most commonly for milk and orange juice.
In reference to 1.5x ''conversion'' factor proposed by Dr Fackler (that you seem to be referring to) on page 21 of the Fall 2001 issue of the IWBA Journal of Wound Ballistic Review: 5;2, Dr Fackler points out the limitation of using a simple linear conversion value by making it clear that there is some inherent inaccuracy in its use—''Most bullets will penetrate about 1.5 times as farther in water as in standard 10% ordnance gelatin: some penetrate even farther.'' More to the point, simple linear conversion values do not consider the influence of physical effects of drag, test medium density and strength, bullet diameter, mass, and/or velocity upon the maximum terminal penetration depth of a bullet.
The employment of mathematical bullet penetration equations—all of which consider the effect of drag, test medium density and strength, bullet diameter, mass, and velocity in their respective forms—greatly reduces the error in such predictions often to within a small fraction of an inch. While water does slightly over-drive projectile expansion, its effect upon the accuracy of these equation's predictions is minimal.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Hello Sir,
It was only early on in the thread that you included the E15 EKE data..
With the .327 Gold Dot and the 230+P is where a fairly large increase of EKE is present or the larger negative number
What I am really curious to see is any data on 125 gr .357 Mag or .357 Sig, 155 or 165 gr .40 increase over 180s, or if some 185+P's EKE is greater than standard pressure 230's...or say how much difference +p+ like 9bple is over standard pressure 9bp?
Can you please provide me any E15/EKE numbers of these faster rounds please?
I expect some of these pass -350 or get close to it...especially the 125 gr .357s and faster 155/165 gr 40s....which is quite a bit difference than say a standard pressure 115 or 124 gr 9mm.
While they lighter for caliber rounds generally may have less lead to spread, a bit less expanded diameter then their heavy for caliber counterparts, and therefore less Tissue Crush/Would Volume
...It seems to be that these faster rounds that I am guessing had more EKE, in real world OIS/DGU often had very successful effect, at least when there were no intermediate barriers present nor was it a side lateral shot through the arm first. While in shots through the later criteria, often present in the LE context, 15" of Penetration may be ideal.
However in the former more frontal shots that didn't require going through a barrier or arm first 11" of Penetration, huge expansion, large EKE & all energy being deposited inside the body may may have mostly worked great especially before better bullet technology and may still work great for the None LE situations .
I'm hypothesizing that something in-between, 13" of Penetration, larger expansion, larger Wound Volume before being stuck in the skin on the back or exiting, More EKE and more Energy in the body....
May be more ideal MORE OFTEN then then rounds with less expansion & 15-18" of Penetration (other than for those dealing with vehicles more often/state police etc.)
IE while Gold Dot, or perhaps Critical Duty may be better for Law Enforcement depending on the job duties
HST seems to be the best for Civilians overall
But 125 gr SJHP .357 Magnum, then to a lesser effect 9ple or other 115+p+, later .357 Sig 125 gr seemed to have worked great in most cases and with the two former...it wasn't huge penetration or huge expansion compared to others (or heavier for caliber 158s and 147's)
EKE seems to me to be this other thing that may matter...at least most of the time...
Last edited by Ghost Dog; 03-29-2024 at 10:11 PM.
Whether you set you Penetration Parameter minimum at 11" or 12" or 13"
It would be nice if in different Calibers, and averages of say 5 rounds of the various bullet weights Light/Medium/Heavy were done in 9/40/45, and .327/.357 Magnum & .357 Sig whatever data is available...
Mr. Schwartz can you please Average 3 or 5 rounds by bullet weights and provide, even if in PM, the Would Volume and EKE please?
To see on average which bullet weights give the largest 1. Wound Volume & 2. Most EKE
It seems Heavy for Caliber is often the recommended, but perhaps that was with older Cup N Core bullets to ensure adequate penetration.
Is a Faster Medium weight for caliber perhaps better, at least with higher tech bullets that barely fragment?
And whey did extremely fast but light for caliber bullets...often work, at least in frontal non barrier shots?
If wound volume is fairly close, is one with more EKE desired? I'd like this data if possible.
IE I have tended towards 124+ over 147 in general and more specifically HST if available (though out of all 147s it seems HST seems the best out of all barrel lengths)
180 (HST) over 165, though I wonder if Wound Volume is similar, and wonder if the 165 (or even old 155 if you can find it) had more EKE?
I'm also curious if 185+P give similar enough Wound Volume, but more EKE, then 230 grain which by having more lead to spread greater expansion is it therefore a much greater Wound Volume or is it actually fairly close?
To me, "heavy for caliber" is better so that there is more bullet material to convert into greater expansion while also helping to keep penetration depth good through increased mass. Once a good penetration depth is achieved, then expansion increases can be achieved through more bullet material/mass. Remember that energy is not a reliable component of wounding effectiveness, a projectile has to physically disrupt structures to be reliably effective.
Using manufacturer's 10% ordnance gelatin test data, I'll attempt to provide some reference points for you.
ΔE15 = -320.13 fpe
ΔE15 = -295.25 fpe
ΔE15 = -335.23 fpe
ΔE15 = -325.25 fpe
ΔE15 = -415.56 fpe
I hope that this post answers some of the questions that you've asked.
Last edited by the Schwartz; 04-02-2024 at 04:40 PM.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Thank you, I will have to compare tomorrow to some of the rounds you gave earlier in the thread. Ie looking for 124+P HST vs 147 HST (and would love the eke on 9bple or other 115+p+ to compare), and 185 say Gold Dot vs 230 gold dot.
Thank you again, sorry to ask for more but is there any chance of providing the E15/EKE for 147 HST, 230 Gold Dot, 230 HST, and any 115+p+ as a comparison (Winchester gave their data on the Ranger, though I don't believe Federal ever did)? That would help me understand some things.
I do know many here like heavy for caliber, yet a lot of depts issue 124+P mostly Gold Dots I assume, or 135+p Critical Duty, though I wonder if more departments have gone to 147 HST, if that is cheaper than the gold dots, and also now penetrates farther since double cannelure added?
Just would like to have that data on different bullet weights, again if adequate penetration is reached (which 9bple doesn't penetrate very far but was very successful in most cases all over for a long time)
It seems the .45 crowd just sticks to 230, but shorter than 4-4.25" barrels the only 230 I see expand at low threshold is HST. For short barrels I do think many would be served better with 185s, and perhaps lower recoil in the smaller lighter 45 carried by AARP members...
I wish I knew how to figure E15/EKE from published data, is it a fairly easy formula to apply if you know bullet weight and velocity, as well as penetration and expansion?
On charts I have seen, am I correct that almost always with a pistol jhp you are looking at a bit over half of ME is lost by the 15cm mark? (That's probably the same for 5.56 too depending on bullet type, say a 193 that yaws and frags, but maybe not larger over .30 rifles & I know that is very dependent on projectile type?)
How much of a wider wound is there torn flesh the first few inches...say in a deer hit with a .357 hit at 1500 fps from 4-6" Revolver vs one hit with a 1200 fps by .355 9mm Pistol where legal to do so?
From high speed footage, is that what would be shown in Organic Gel and taken into consideration when calculating Wound Volume? So it's not just the r2 and depth, but also some actual tearing the first few inches of the wound adding to wound volume? I know we are not talking rifles, but there is a difference in the first few inches of the wound that adds to overall wound volume in those formulas, if seen in the gel on high speed cameras?
In both pistols, and rifle calibers I've heard many prefer that short neck for either expansion or Yaw (heavier 75-77 grain yaws later but that is still around lung penetration depth I believe when that happens hence effective and probably a sideways keyhole large exit out BGs back is my guess is what has been found though I don't know if that is true?)
That .357 Sig HST I have to assume will generally have VERY good effectiveness, where as the gold dot is likely better dealing with vehicles, but I know of two instances that .357 LE Gold Dot had ACTUAL Overpenetration of the BG. There was a Personal Defense Gold Dot that I believe had more like around 13" of Penetration.
Similarly I think it was the .45+p Ranger T that had a large EKE number you provided early in the thread.
It's hard for me to think that a round that gives adequate 1. Penetration for the task/duty 2. Expansion 3. Wound Volume that then higher EKE wouldn't be desired.
Last edited by Ghost Dog; 04-02-2024 at 07:29 PM.
Although they don't directly answer your questions, you might find these links interesting and somewhat relevant...
https://brassfetcher.com/Wounding%20...Expansion.html
https://www.ballisticstudies.com/Kno...57+Magnum.html
"As a general guide to performance, the .357 can produce quite spectacular kills at impact velocities of 2000fps and faster using hollow point projectiles.
At impact velocities of 2000 to 1600fps, game hit with a fast expanding hollow point tend to react in a drunken manner, often attempting to run but not generally making too much ground before succumbing quickly to blood loss.
Between 1600 and 1300fps, dead runs may be longer but wounding is still somewhat disproportionate to caliber. Again, bullet weights must be matched to the job at hand. If the bullet is too heavy, it may not meet enough resistance to render a wide wound at low velocities. If the bullet is too light, it may not have enough energy to render a deep and broad wound on larger bodied animals.
At impact velocities of 1200fps and below, bullet expansion may be fully evident, yet wounding can be narrow (proportionate to the expanded caliber of the bullet) and blood trails poor. At these velocities and in the absence of any major hydraulic force, the .357 is reliant on mechanical wounding, the size of the wound being directly proportionate to the diameter of the expanded bullet."
Reply With Quote
