Does Energy Count In Handgun Calibers?

The only time foot pounds of energy doesn't "count" is for some of the games where numbers/formulas have to be jiggered to make "major", thus making your .45 viable. lolz

Well, all else being equal. A heavier wadcutter isn't going to run down a boat-tail spitzer just because it's 10 grains heftier.

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Well...I assumed that everybody understood that I meant with identical bullet shapes...but I guess some people will look for anything to nit-pick.

Of course we will!

Just trying to give full effect to your admonition that "everything is something." Bullet shape is something. It may not be material, but I'm not sure that decay of velocity is material at defensive handgun (which is what this thread seems to be about) ranges, either. I could be wrong, though.

I voted "no", but this is a bit of a complicated question. The energy obviously matters in that you need the energy to drive the work, including penetration and possibly expansion; and excess energy for what's needed causes extra recoil. However, in handgun calibers, it's not the energy transfer itself that is causing the permanent damage; it is the mechanical actions of the bullet crushing through tissue. Bullet design is going to be a much bigger factor in wounding potential than the energy provided, especially if you use standard loads. I prefer to look at the terminal ballistics instead of the external ballistics.

Quote:
Originally Posted by CZ57 View Post
Well, I'm glad you could find 1 example. There are +P loads available from Double-Tap, Buffalo Bore that are rated 1125 FPS or higher and Underwood Ammo has a 147 gr. JHP rated at 1175 FPS and +P+. They all use bonded bullets. Stick that in your theoretical Mcpherson modeler.


Now, now......there's no need to be rude. I'd remind you of rule 4 of the THR CoC, posted here for your convenience-

4. Spamming, trolling, flaming, and personal attacks are prohibited. You can disagree with other members, even vehemently, but it must be done in a well-mannered form. Attack the argument, not the arguer.

Do try to be civil.

If you have misgivings or lack an understanding of these models (Schwartz, MacPherson), you might do yourself a favor and read one or two of the two books.

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So now your the conduct police because you know what the result of using the higher energy loads will do in the modeler? Who's being rude? All I said was "stick that in your MacPherson modeler". I think everyone here can recognize someone's attempt to be a subtle smartass.

MacPherson's theories put forth the notion that bullets behave like flying drill-bits. I guess that's because he's a mechanical engineer as well as a Facklerite. It seems that anyone with an interest can become a terminal ballistics expert these days. But go back to the case of the 147 gr. HST vs. the 147 gr. +P HST, since that's the load you seem to understand. The +P penetrates only 3/10" deeper and by MacPherson's model all that will achieve is to cut the wound cylinder by 86% of recovered diameter with a depth of 3/10" in addition to the permanent crush cavity created by the standard pressure 147 gr. HST. That's it and all he considers.

What is not considered in the model is the point where expansion begins, rapidity of expansion, the larger temporary stretch cavity created causing a larger Total Wound Volume. Again, without the actual representation showing the two rounds fired into ballistic gelatin your assumptions are simple hyperbole.

I only introduced the Critical Duty 135 +P into the conversation as a lower recoil option for those that may be recoil sensitive. But at least there is actual gel tests that can be viewed at the Hornady site. You, on the other hand have provided nothing but conjecture along with a recommendation to read two books. One of which I already know to be seriously flawed.

I also posted a link to m4carbine.net where anyone can go to see a ballistic gel test of various loads including on of the better performing standard pressure 147s and a standard pressure 124. No need to even see a 124 +P because the standard pressure 124 is out performing the standard pressure 147. There, at least, the viewer can decide for himself which is the better performing load.

One thing I can say for the 147 gr. JHP is that it's sectional density is very high due to it's length and .355" diameter. It is actually less dependent on KE than the 124 because it is capable of higher momentum at the right velocity. So lets use the simple method of comparing power factor of the two loads that is fairly representative of momentum. Your 147 gr. HST with a muzzle velocity of 1000 FPS has a power factor of 147. I'll use the example of the SPEER 124 gr. +P Gold Dot which is rated 1220 FPS at the muzzle and has a power factor of 151. The 147 develops 326 Ft/Lbs of KE at the muzzle. The 124 gr. +P Gold Dot develops 410 Ft/Lbs at the muzzle. So not only does the 124 have a greater amount of KE it also provides higher momentum than the 147 that's more dependent on momentum for expansion. The differences can be seen by examining rounds fired into %10 ballistic gelatin. So if I expected a 147 to perform as well as a 124 +P, I'd choose a 147 gr. +P.

And what I meant about "serious shooters" is that anyone contemplating carrying a handgun for self defense should be able to master the 124 gr. +P. They should practice until they can. If that doesn't work and you still decide to carry concealed, then go with a standard pressure 147. And before someone brings up something like accelerated wear by use of +P ammo, I'll remind everyone that when I started shooting and handloading 9mm, there was no +P. There was the pressure standard that had been in use since 1902 and that is 35,700 CUP. Test a similar load by the SAAMI PSI method and you'll find it achieves about 38,500 PSI. The SAAMI rating for +P. The European standard of 36,200 PSI CIP is almost an identical pressure they just use a slightly different test method. You can bet that any quality American or European manufactured 9mm Pistol is designed around the original pressure standard of 35,700 CUP. The difference being that pistols intended for the American market are sprung lighter.

What is not considered in the model is the point where expansion begins, rapidity of expansion, the larger temporary stretch cavity created causing a larger Total Wound Volume.

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Both controlled by bullet design, not by fifty or a hundred feet per second here or there.

I don't think a temporary stretch cavity caused by bullets of the size, weight, and speed we're talking about here have much impact on the final wound either. Flesh is plenty elastic.

Bullet design accounts for the differences between final measurements of handgun wounds far more than specific weights and velocities do.

CZ57 said:

So now your the conduct police because you know what the result of using the higher energy loads will do in the modeler? Who's being rude? All I said was "stick that in your MacPherson modeler". I think everyone here can recognize someone's attempt to be a subtle smartass.

MacPherson's theories put forth the notion that bullets behave like flying drill-bits. I guess that's because he's a mechanical engineer as well as a Facklerite. It seems that anyone with an interest can become a terminal ballistics expert these days. But go back to the case of the 147 gr. HST vs. the 147 gr. +P HST, since that's the load you seem to understand. The +P penetrates only 3/10" deeper and by MacPherson's model all that will achieve is to cut the wound cylinder by 86% of recovered diameter with a depth of 3/10" in addition to the permanent crush cavity created by the standard pressure 147 gr. HST. That's it and all he considers.

What is not considered in the model is the point where expansion begins, rapidity of expansion, the larger temporary stretch cavity created causing a larger Total Wound Volume. Again, without the actual representation showing the two rounds fired into ballistic gelatin your assumptions are simple hyperbole.

I only introduced the Critical Duty 135 +P into the conversation as a lower recoil option for those that may be recoil sensitive. But at least there is actual gel tests that can be viewed at the Hornady site. You, on the other hand have provided nothing but conjecture along with a recommendation to read two books. One of which I already know to be seriously flawed.

I also posted a link to m4carbine.net where anyone can go to see a ballistic gel test of various loads including on of the better performing standard pressure 147s and a standard pressure 124. No need to even see a 124 +P because the standard pressure 124 is out performing the standard pressure 147. There, at least, the viewer can decide for himself which is the better performing load.

One thing I can say for the 147 gr. JHP is that it's sectional density is very high due to it's length and .355" diameter. It is actually less dependent on KE than the 124 because it is capable of higher momentum at the right velocity. So lets use the simple method of comparing power factor of the two loads that is fairly representative of momentum. Your 147 gr. HST with a muzzle velocity of 1000 FPS has a power factor of 147. I'll use the example of the SPEER 124 gr. +P Gold Dot which is rated 1220 FPS at the muzzle and has a power factor of 151. The 147 develops 326 Ft/Lbs of KE at the muzzle. The 124 gr. +P Gold Dot develops 410 Ft/Lbs at the muzzle. So not only does the 124 have a greater amount of KE it also provides higher momentum than the 147 that's more dependent on momentum for expansion. The differences can be seen by examining rounds fired into %10 ballistic gelatin. So if I expected a 147 to perform as well as a 124 +P, I'd choose a 147 gr. +P.

And what I meant about "serious shooters" is that anyone contemplating carrying a handgun for self defense should be able to master the 124 gr. +P. They should practice until they can. If that doesn't work and you still decide to carry concealed, then go with a standard pressure 147. And before someone brings up something like accelerated wear by use of +P ammo, I'll remind everyone that when I started shooting and handloading 9mm, there was no +P. There was the pressure standard that had been in use since 1902 and that is 35,700 CUP. Test a similar load by the SAAMI PSI method and you'll find it achieves about 38,500 PSI. The SAAMI rating for +P. The European standard of 36,200 PSI CIP is almost an identical pressure they just use a slightly different test method. You can bet that any quality American or European manufactured 9mm Pistol is designed around the original pressure standard of 35,700 CUP. The difference being that pistols intended for the American market are sprung lighter.

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Nope, I'm not the "conduct police", but I do recognize rudeness when I see it. Such behavior is indicative of an unhealthy emotional investment in the topic and your defensiveness, not to mention your misrepresentation of MacPherson's model, confirms it.

Since you continue to resort to such behavior, I see no value in continuing any further with you.

Done.

I see no value in you ever have becoming part of this thread.

Both controlled by bullet design, not by fifty or a hundred feet per second here or there.

I don't think a temporary stretch cavity caused by bullets of the size, weight, and speed we're talking about here have much impact on the final wound either. Flesh is plenty elastic.

Bullet design accounts for the differences between final measurements of handgun wounds far more than specific weights and velocities do.

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Try this then, consider the doctrine of people like Martin Facler, Roberts the Dentist and MacPherson the mechanical engineer. They don't believe that the temporary stretch cavity has any significance in wounding either. Try getting them to explain why you can get equal expansion and greater depth of penetration with a 158 gr. JHP in .357 Magnum, yet the 125 gr. JHP in .357 Magnum with its higher KE is a better stopper. The first thing any of them will start is a diatribe on how flawed the statistical data is with Marshall & Sanow's Street Stoppers. Marshall & Sanow both admit that they are not scientists and that the one shot sop data is not science, nor a tactical philososphy. It's simply a reporting of events where a police officer expended one round to stop a fight where either the perp stopped aggression immediately or failed to move over about 10' from his aggressive position. Among all of the reports, the 125 gr. JHP in .357 Magnum has been the most effective round in LE history.

This is where the KE model falls apart;

http://www.glocktalk.com/forums/showthread.php?t=336612

Compare the KE advantage of the 10mm/180gr Gold Dot with the 45auto/230gr Gold Dot, same penetration and expansion. Check the 230gr Gold Dot with the uber high velocity 9x25mm/125gr Gold Dot, slight penetration advantage for the 45auto, but a sizable crush cavity advantage for the heavy and "slow".

I guess I don't get it. At the link you provided I don't see any gel test pics, just a list of cartridge performance after passing through four layers of denim and two layers of light cotton.

Both the rounds you mention penetrate to 15.25". The 230 gr. Gold Dot expands to .95" and the 180 gr. 10mm expands to .96". According to the beliefs of experts like Fackler, MacPherson and Roberts, you throw energy and temporary stretch cavity out the window and in this case the 180 gr. 10mm by their standards would be the better stopping load by virtue of .01" greater expansion.

2zulu1 said:

This is where the KE model falls apart;

http://www.glocktalk.com/forums/showthread.php?t=336612

Compare the KE advantage of the 10mm/180gr Gold Dot with the 45auto/230gr Gold Dot, same penetration and expansion. Check the 230gr Gold Dot with the uber high velocity 9x25mm/125gr Gold Dot, slight penetration advantage for the 45auto, but a sizable crush cavity advantage for the heavy and "slow".

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As usual, 2z1, your comprehension of the salient issues is excellent.

Kinetic energy, while it plays a part in how a bullet behaves, is the least efficient/appropriate way to analyze terminal performance as both MacPherson (an MIT educated aerospace engineer) and Schwartz explain below:

Excerpt from Bullet Penetration by MacPherson:

“. . . every now and then someone wants to analyze or think about a problem involving energy, and when they attempt to do this without really understanding energy or other thermodynamic concepts the result is unfortunate. One such problem is the analysis of any of the various aspects of terminal ballistics; some individuals with inadequate technical training and experience have unwisely and unproductively attempted to use energy concepts in the analysis of bullet impact and penetration in soft tissue. (Many others have simply assumed that energy is the dominant effect in Wound Trauma Incapacitation; this assumption is even more simplistic than the attempt to actually analyze the dynamics problem with energy relationships, and is no more successful).

Any attempt to derive the effect of bullet impact in tissue using energy relationships is ill advised and wrong because the problem cannot be analyzed that way and only someone without the requisite technical background would try. Many individuals who have not had technical training have nonetheless heard of Newton’s laws of motion, but most of them aren’t really familiar with these laws and would be surprised to learn Newton’s laws describe forces and momentum transfer, not energy relationships. The dynamic variable that is conserved in collisions is momentum; kinetic energy is not only not conserved in real collisions, but is transferred into thermal energy in a way that usually cannot be practically modeled. The energy in collisions can be traced, but usually only by solving the dynamics by other means and then determining the energy flow.

Understanding energy and how it relates to bullet terminal ballistics is useful even though energy is not a useful parameter in most small arms ballistics work.”

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Excerpt from Quantitative Ammunition Selection by Schwartz:

While a projectile in motion possesses both momentum and kinetic energy, the penetration of a transient projectile through a homogenous fluid or hydrocolloidal medium constitutes an inelastic collision mandating that it be treated as a momentum transaction. Therefore, a momentum-based analysis of projectile motion is the most equitable approach in constructing a terminal ballistic performance model. Although it may be possible to devise a mathematical model based upon the expenditure of a projectile’s kinetic energy as it traverses a medium, there is nothing to be gained from the pursuit of such an unnecessarily complex approach.

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Theory and conjecture. Thanks for pointing out that MacPherson is an aerospace engineer. He should stick to his trade. His hypothesis are only tested by theoretical models, or are directly traceable back to the philosophy of Martin Fackler. And for those that don't know, it was Martin Fackler's theories dominated by penetration that led the FBI and other LE agencies to choose the 147 gr. JHP 9mm load in the late 80s. These rounds failed to provide adequate expansion and in some cases innocent bystanders were struck by overpenetrating bullets. Then came the "10mm Lite" based on the same principles dominated by penetration that proved to be only a marginal stopper in actual shootings. Marshall & Sanow's reports rated it at around 80% effective while the measuring stick for all LE ammo was the 125 gr. JHP in .357 Magnum with three different loads coming in at 96%.

Next on the Fackler hit parade came the "Medium Velocity" 165 gr. JHP load in .40 S&W. Another lackluster performer that didn't last long. All of this at taxpayer expense, by the way. Rather than correct his own mistakes, Fackler and his followers began a crusade against the data collection method of Marshall & Sanow. Two police officers and laymen that simply compiled reports where only one shot was required to stop a fight by LE officers across the country. When you think about it, it's not much different from ballistic gel testing. Only one round can be examined at a time in order to compare it to any other tested round/caliber.

Part of Fackler's history might help explain some of his theories. He's a former Army doctor who had actual experience in treating wounds on the battlefield. The battlefield where only full metal jacket projectiles are used and jacketed hollow-points are forbidden and not used. He also examined some shootings where JHPs had been used but they were post-mortem and corpses do not provide the best representation of what occurs in a gun battle.

The one conclusion that Fackler arrived at and is very useful today is the minimum 12" of penetration standard. I think we can all agree that expansion is a very important factor in the wounding process. Penetration without expansion, well, you might as well use FMJ ammo. Expansion without penetration as we learned from the 1986 "Miami Shootout", also ends up with negative results. Heavier bullets definitely have a momentum advantage. For a lighter bullet to have as much momentum as a heavier one it must have higher velocity and KE. A 155 gr. JHP at 1200 FPS in .40 S&W that penetrates 12" after barriers is as good or better than a subsonic 180 gr. load just as a 124 gr. +P 9mm developing higher KE as well as higher momentum compared to a standard pressure subsonic 147, the 124 gr.+P will be the better stopper. The only subsonic round I'd consider for use is the 230 gr. JHP in .45 ACP traveling at 900 FPS or better. It is not as dependent on KE because of its high momentum, nonetheless, it achieves more than 400 Ft/Lbs of KE and falls into the window I mentioned in my earlier post with 400 - 600 Ft/lbs being the most effective range for defensive handgun rounds. This has proven the be the case when examining one shot stop data. Actual shootings, not unproven theories.

Bullet technology has definitely improved but I believe the 400 - 600 Ft/Lb window is still valid. So it's this simple; choose a load that has proven to provide a minimum 12" of penetration after passing through 4 layers of denim while achieving 400 - 600 Ft/Lbs of KE regardless of bullet weight because momentum can be provided in two different ways. Heavy bullets with enough velocity to achieve 400 Ft/Lbs of KE like the 230 gr. JHP in .45 ACP, or a lighter bullet that may need to be closer to the high end of 600 Ft/Lb as in the case of the 125 gr. JHP in .357 SIG or Magnum.

Let the theorist play their games because in the end it is only theory. Nothing has been proven empirically. For every theoretical opinion you consider you should also consider the one shot stop data where reality has proven what works and what doesn't.

CZ57 said:

I guess I don't get it. At the link you provided I don't see any gel test pics, just a list of cartridge performance after passing through four layers of denim and two layers of light cotton.

Both the rounds you mention penetrate to 15.25". The 230 gr. Gold Dot expands to .95" and the 180 gr. 10mm expands to .96". According to the beliefs of experts like Fackler, MacPherson and Roberts, you throw energy and temporary stretch cavity out the window and in this case the 180 gr. 10mm by their standards would be the better stopping load by virtue of .01" greater expansion.

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In post #63 you used Double Tap, Buffalo Bore and Underwood ammunition to support a statement, yet you didn't post any ballistic gel pictures. I post DT's gel data and now you need pics, why the double standard?

It's interesting that you should denigrate MacPherson and at the same time want pictures of bullet performance in ballistic gel. Guess what, it was MacPherson who did the research, bullet testing and came up with the formulas that validated Fackler's ballistic gel composition as a soft tissue simulant. It doesn't seem to me that a person who conducts the tedious and time consuming tasks of shooting 400 rounds of ammunition, into an aggregate total of a ton of ballistic gel, be considered a theorist.

You can't have it both ways, if you accept the use of ballistic gel as a medium to determine bullet penetration in soft tissue, then you accept MacPherson's research. If you don't accept MacPherson's research, then you can't use ballistic gel as a test medium.

Either accept MacPherson's kinetic energy quote as posted by 481 or find a testing medium other than ballistic gel. BTW, MacPherson's book has pictures of bullets in it, the book by Schwartz doesn't, but both are excellent references for those who wish to intelligently discuss terminal ballistics.

The purpose and composition of ballistic gel is to measure bullet penetration in soft tissue, that's all.

There's a lot of excellent information at this website, I linked to this "myth" chapter because of its appropriateness to this thread.

http://www.rathcoombe.net/sci-tech/ballistics/myths.html#energy

I'm in the mass x velocity, big fat bullet and momentum camp...

2zulu1 said:

.If you don't accept MacPherson's research, then you can't use ballistic gel as a test medium..

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Sure you can. You can shoot the test medium with a 125 grain .357 and then logically, all ammo that didn't perform like that/have those characteristics would essentially be inferior since it's the undisputed stopper.

2zulu1 said:

In post #63 you used Double Tap, Buffalo Bore and Underwood ammunition to support a statement, yet you didn't post any ballistic gel pictures. I post DT's gel data and now you need pics, why the double standard?

It's interesting that you should denigrate MacPherson and at the same time want pictures of bullet performance in ballistic gel. Guess what, it was MacPherson who did the research, bullet testing and came up with the formulas that validated Fackler's ballistic gel composition as a soft tissue simulant. It doesn't seem to me that a person who conducts the tedious and time consuming tasks of shooting 400 rounds of ammunition, into an aggregate total of a ton of ballistic gel, be considered a theorist.

You can't have it both ways, if you accept the use of ballistic gel as a medium to determine bullet penetration in soft tissue, then you accept MacPherson's research. If you don't accept MacPherson's research, then you can't use ballistic gel as a test medium.

Either accept MacPherson's kinetic energy quote as posted by 481 or find a testing medium other than ballistic gel. BTW, MacPherson's book has pictures of bullets in it, the book by Schwartz doesn't, but both are excellent references for those who wish to intelligently discuss terminal ballistics.

The purpose and composition of ballistic gel is to measure bullet penetration in soft tissue, that's all.

There's a lot of excellent information at this website, I linked to this "myth" chapter because of its appropriateness to this thread.

http://www.rathcoombe.net/sci-tech/ballistics/myths.html#energy

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2z1,

Hadn't run across the rathcoombe 'site before. Lots there to digest. Thanks.

I also find it funny (and hysterically so) that those who'd dismiss without any reasonable basis the empirical research found in Quantitative Ammunition Selection and Bullet Penetration are so quick to hold up Marshall & Sanow as an examplar of how empirical research should be conducted given the numerous analyses that reveals that M&S manipulated their data in order to arrive at a desired conclusion, unless of course, one considers one chance in 3.25 trillion to be "good odds" that M&S actually conducted a legitimate piece of research.

http://firearmstactical.com/briefs24.htm#TooGoodToBeTrue

http://firearmstactical.com/marshall-sanow-discrepancies.htm

http://firearmstactical.com/sanow-strikes-out.htm

What's even funnier is when the empirical research done by any other researcher is dismissed out-of-hand as "theory and conjecture" and then in the same breath utters as an example, the names of Marshall & Sanow- arguably two of the worst offenders where data manipulation is concerned.

FBI barrier test

The FBI doesn't select a product based directly on energy calculations. Their selection is based on the bullet's performance in gelatin (eight different tests), accuracy and pressure. The barrier tests are the most important with bullet penetration accounting for 67% of the total penetration score. Bullet weight retention and expansion each account for approximately 16% each.

Energy obviously plays a part in bullet penetration, but more energy isn't always a good thing since it can reduce bullet penetration depending on how the bullet expands on contact with a barrier or tissue.

The short version is that energy does "count" in how a bullet performs but it's just one variable.

Theory and conjecture. Thanks for pointing out that MacPherson is an aerospace engineer. He should stick to his trade.

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Why? What’s your background?

His hypothesis are only tested by theoretical models, or are directly traceable back to the philosophy of Martin Fackler.

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And for those that don't know, it was Martin Fackler's theories dominated by penetration that led the FBI and other LE agencies to choose the 147 gr. JHP 9mm load in the late 80s. These rounds failed to provide adequate expansion and in some cases innocent bystanders were struck by overpenetrating bullets.

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The IWBA Handgun Ammunition Specification was developed as an alternative to the FBI Ammunition Tests protocol. The IWBA feels the FBI test program has led to the unfortunate development of handgun bullets that do not expand after passing through heavy clothing. This is due to the FBI’s insistence on testing bullets against various barrier materials (automotive grade sheet metal, drywall, plywood, and laminated automotive windshield glass). The overwhelming majority of bullets designed to perform well in the FBI test program tend to suffer expansion failures when heavy clothing is encountered. This is a common performance deficiency that seems to universally afflict all cartridges across the board.

Then came the "10mm Lite" based on the same principles dominated by penetration that proved to be only a marginal stopper in actual shootings.

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The “10mm Lite” was the model for the .40 S&W 180gr load, which has performed very well in actual shootings. 180gr is to .40 S&W what 230gr is to .45 ACP. Both bullet weights have the same sectional density, but .40 S&W (“10mm Lite”) is propelled at slightly higher velocity.

Next on the Fackler hit parade came the "Medium Velocity" 165 gr. JHP load in .40 S&W. Another lackluster performer that didn't last long. All of this at taxpayer expense, by the way. Rather than correct his own mistakes, Fackler and his followers began a crusade against the data collection method of Marshall & Sanow. Two police officers and laymen that simply compiled reports where only one shot was required to stop a fight by LE officers across the country.

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You mean like this? http://www.firearmstactical.com/briefs8.htm

And this?: http://www.firearmstactical.com/pdf/sanow.pdf

BTW, Fackler had nothing to do with the .40 S&W 165gr “medium velocity”.

Consider this:

We're talking about self defense, so we're talking about shooting human threats.

With that in mind....

There is no way to reliably predict the penetration of any given round in a shooting.
There are far too many variables at play (size of the threat, body composition of the threat, angle of the shot in relation to the threat's body, clothing worn by the threat, etc...).

There is no way to reliably predict the expansion of any given round in a shooting.
Again, too many variables.


But one can buy ammo that can reliably offer an approximate muzzle energy.


So, why would one discount energy in favor of other far less reliable factors?

easyg said:

But one can buy ammo that can reliably offer an approximate muzzle energy. So, why would one discount energy in favor of other far less reliable factors?

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I think it's fair to assume that the FBI is under considerably more pressure to "get it right" than the rest of us, and they don't select ammunition based on muzzle energy.

1858 said:

I think it's fair to assume that the FBI is under considerably more pressure to "get it right" than the rest of us, and they don't select ammunition based on muzzle energy.

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That's a good point, 1858.

The criteria for a bullet to pass the FBI tests is that it can pass the different test events- it's not like the FBI screens ammunition based on its KE and tests whatever remains after that. I do not believe that there is a KE requirement in the FBI test procedure.

481 said:

I do not believe that there is a KE requirement in the FBI test procedure.

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Correct!! There isn't even a direct velocity requirement, "just" penetration, weight retention, expansion, accuracy and pressure.

I heard the FBI is going back to the 9.