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9mm vs. .45 - but different!

Discussion in 'Handguns: Autoloaders' started by Philip Marlowe, Apr 22, 2009.

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  1. Philip Marlowe

    Philip Marlowe Member

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    During a training session, our instructor threw out some large hard-rubber blocks, about 10 yards away from our group (two groups of 4, actually).

    The goal was for each group to move their blocks a certain distance.

    It just so happened that one group was entirely .45 autos (a RIA, Kimber, XD, and something else) and our group was all 9mm, save one guy (S&W1911).

    Prior to this, we'd all been shooting near equal, with two of the 9mm shooters grouping FAR better than the rest (one guy tearing cloverleafs in the target was running a Beretta 92fs).

    Long story short - the .45 team moved the block MUCH faster, and each shot they hit sent the block further than our hits with 9mm.

    In fact, the 9mm barely budged this stubborn rubber block.

    I typically shoot 9mm, so this isn't a 'caliber battle' but I just thought it was symbolic and definetly something to learn from (hence why I just bought my first .45).

    I know that shot placement is always #1 on the list, but I was wondering if anyone else has had similar experiences? Something that made you rethink the caliber of your handgun? No my example isn't scientific, but it did make me think.
     
  2. chris in va

    chris in va Member

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    I guess one reason why 45 is popular with the pin shoots.
     
  3. TheVirginian

    TheVirginian Member

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    All I wanna know is what kind of an "instructor" asks a group of 8 people to fire at a hard rubber block at 10 yards? He's definitely not an Aussie or he'd have heard about a boomerang...
    -Bill
     
  4. ArmedBear

    ArmedBear Member

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    Yes.

    I shot a North American Bison with a Sharps rifle and a black powder load, dropped it in one shot, then butchered it and looked at the entry, exit and wound channel.

    Until you hit Roy Weatherby velocities, small bullets are just that: small bullets.

    At handgun/black powder velocities, a big heavy bullet wins.

    Those who think that the 9mm, no matter WHAT modern enhancements it might have, is "as good as" or "as powerful as" a 230 grain .45 with a decent bullet design (RNFMJ has inherent problems), haven't seen what a big bullet does.

    There are reasons to use 9mm or .38 Special, but I do not expect them to do what a good 230 grain .45 bullet will -- because they won't.
     
    Last edited: Apr 23, 2009
  5. Rancho Relaxo

    Rancho Relaxo Member

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    Good to know for when the rubber blocks attack.

    Seriously though, that's pretty interesting. I'm a died in the wool 9mm guy regardless.
     
  6. ArmedBear

    ArmedBear Member

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    BTW what you saw with the rubber blocks, and what I saw with the bullet that went straight through the buffalo was the effect that momentum has.

    The 9mm rounds probably have close to the same energy as the .45ACP rounds in the rubber block shooting experiment. But they didn't move the blocks.

    That's why IMO energy is BS, most useful for marketing little bullets and making them appear to be "as good as" big ones. They're not. A couple hundred FPS doesn't turn a 115 grain bullet into a 230, end of story.
     
  7. patrick526

    patrick526 Member

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    I wished they've compared the 9mm HST/Gold Dot/JHP to the .45 FMJ.
     
  8. Vonderek

    Vonderek Member

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    Good to know...gonna build a vest out of rubber blocks...
     
  9. saturno_v

    saturno_v Member

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    Maybe the 9 mm was penetrating the block better resulting in less "push"


    The "Roy Weatherby velocities" are not a some sort of magical barrier...

    It's the law of physics....energy increase exponentially with velocity...energy is the ability to do work...it doesn't matter if is at handgun velocity or super-duper magnum rifle speed.

    Momentum would matter more in a vacuum...in the real world there are thousands of factors and variables that induce drag (frontal area, bullet shape, bullet construction once penetration begins, etc...).....

    This is one of the reason you never find the momentum mentioned in any serious firearm publication....what you find published are BC, SD and energy...The Taylor KO formula is just a theory...


    The 45 ACP ball will create a wider wound channel compared to a 9 mm ball...this is the only irrefutable truth about big bullets Vs, small bullets argument....a 230 gr. 45 ACP ball bullet has higher SD compared to a 115 gr. 9 mm ball bullet....if they strike with the same energy, all other things being equal, the 45 slug will penetrate more....
     
    Last edited: Apr 23, 2009
  10. LoneCoon

    LoneCoon Member

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    F=M*A

    Only when 9mm is moving at twice the speed of .45, it just begins to have the same force. You start ramping up the velocities for .45, the 9mm can't even keep up.

    That said, use what you have and like.
     
  11. saturno_v

    saturno_v Member

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    a 230 gr. 45 slug moving at 850 fps has 368 ft/lb of energy.

    a 9 mm 115 gr. slug will reach the same energy at 1200 fps (350 fps of difference)...so it's not twice the speed....the "twice" relationship is when you take in consideration the bullet weight....a bullet twice the weight of another slug travelling at the same speed will develop twice the energy.
     
  12. jocko

    jocko Member

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    rubber blocks, And who really cares. Bet that instructor can't stick that 45 in his front pocket like I can my Kahr PM9...

    45 cal is a great caliber, so is 50 caliber!!!
     
  13. ArmedBear

    ArmedBear Member

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    I'm sure that was it.:rolleyes:

    Yes, in fact, they are.

    One reason that the Weatherby Magnums, popular "varmint" rounds, the 5.56 NATO, etc. come out of the muzzle at well over 3000 fps is that, at those velocities, you get fluid dynamics happening in the target that just don't happen at pistol velocities. That's how you get exploding prairie dogs, and big game dropping like a stone when hit with the little .240 Weatherby Magnum.

    You can argue all you want about 2500 vs. 3500 fps., which is why I didn't use any specific number. But pistol velocities, around 1000 fps at the muzzle give or take 20%, are nowhere near the velocities where these effects matter. That barrier you say doesn't exist, DOES, at a point somewhere between 1000 fps and 3000 fps. Doesn't matter exactly where.

    Energy doesn't mean much when it comes to effectiveness. Discussing energy in this context is not much different from talking about what color the bullet is.

    And that's the whole point, saturno.

    The reason the 9mm doesn't move the rubber blocks, or a bowling pin, or golf balls, like a .45 is that the bullet doesn't have enough momentum to keep going when it hits an object. If it penetrates, it's because it's got a small diameter, and there's less resistance to its motion -- and therefore less damage to the target, and less effect on the target in general. If a larger, heavier bullet penetrates, it's because it has enough momentum to keep plowing through, causing more damage and greater effect.
     
    Last edited: Apr 23, 2009
  14. jfrey

    jfrey Member

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    If you want to see something move (fly), try shooting golf balls with a .45. A Speer Gold Dot will really make it jump.
     
  15. Thomas Garrett

    Thomas Garrett Member

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    Interesting! I guess i'll have to put rubber block's on my "Hit" list.:what:
     
    Last edited: Apr 23, 2009
  16. mudriver

    mudriver Member

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    My kids and I like to shoot 'stuff' (broken electronics, chipped dishes, old toys) with guns. What we find at the rifle range is that if I load a lead bullet around 1,000 to 1,400 fps the 'stuff' really moves around a lot, jumps, spins, etc.

    However, shoot the same 'stuff' with standard .223, .308 or 7.63x39 and little really happens to it other than create a hole.

    Now, if you fill a plastic bottle with water and do that same comparison you get the opposite results.

    What I gather from this is that the slow lead slugs transfer energy better in non-liquid materials, and small fast bullets transfer better in liquids.

    In conclusion, your instructors comparison is inappropriate since rubber is not, and does not behave like a liquid in ballistic terms.
     
  17. saturno_v

    saturno_v Member

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    ArmedBear

    The Hydrostatic shock theory is what it is...a theory...still not scientifically proven and a weak one to begin with.

    You can read some literature by Dr. Martin Fackler and many other other experts, including several studies done by the FBI

    http://shanoogie.com/l/content/pdfs/shock_wave_myth.pdf

    At most some faint hydrostatick shock effects has been observed in areas just immediately next to the wound.

    Prairie dogs explode because of bullet fragmentation/tumbling :rolleyes:

    Energy is the capability to do work....is one of the most important factors indeed, along with bullet construction and bullet shape....

    Work in this case = capability to penetrate and disrupt tissue.

    The bullet weight is already baked in the energy formula...momentum enthusiasts like to take it out of the cake.....

    You say:

    So the small 9 mm penetrates more....that means tissue disruption...ability to do work.

    More penetration = another form of tissue disruption......tissue is disrupted by more penetration and/or larger wound channel.

    Penetration = more ability to reach the vitals.

    Accordingly with your theory a 45 ACP should be a better stopper than a 357 Magnum...and everybody knows that it's not the case....
     
    Last edited: Apr 23, 2009
  18. Just One Shot

    Just One Shot Member

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    A 9mm in the hand is better than a .45 in the car.
    :neener:













    It doesn't matter how many VS threads there are, you will always have people that will prefer one round over the other.

    Shoot, a .22 is better than a sharp stick or a rock.
    ;)
     
  19. ArmedBear

    ArmedBear Member

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    No, it doesn't.

    It lacks the momentum to overcome the dissipation of energy. It lacks the tendency of an object in motion to remain in motion. When it stops moving, it's doing no more work.

    You keep repeating the same assertions about energy, but you are deliberately IGNORING another number that is at least as important.

    It's easy to make something sound good if you ignore major factors.

    Now you're claiming that the 9mm is MORE effective than the .45ACP because you claim that it penetrates more.

    The problem with your assertion is not the numbers you select, it's that the 9mm is not more effective, and that it doesn't penetrate more, either.

    If your assertions had any merit whatsoever, a .223 bullet going 1400 fps at the muzzle would be as effective against an attacking human target as a 9mm+P round. That's what you're claiming.

    The fact is, a slow-moving 230 grain .45 JHP penetrates as far as a 9mm+P (farther than a small bullet, slightly less than a heavy one, but in neither case by much). And it does a LOT more damage on the way.

    I'm sure you've seen this: http://www.ignatius-piazza-front-sight.com/wp-content/uploads/handgun_gel_comparison.jpg

    That's why energy, the way you're trying to use it, and the way that ammo companies love to have you use it, is BS.

    That was my initial point. I read all that same BS. And I believed it, until I butchered the buffalo. Then I found that reality did not match the BS.
     
    Last edited: Apr 23, 2009
  20. saturno_v

    saturno_v Member

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    Armedbear..you are mixing a lot of things here....

    I never said that a 9 mm is more effective than a 45....bullet stopping power is a VERY complex issues with thousands of variables and factor playing (bullet shape, bullet construction, energy, the target medium etc, etc...the usual stuff)...and the most important of all is shot placement....a 22 LR in the head is going to be more effective than a 357 in the guts....

    Coming back to our 9 Vs 45....the 9 is moving faster so while it has lower momentum it's moving at higher speed ........what it lacks in mass it has in speed...and the smaller diameter will create less drag in the target medium so less dissipation of energy...it will conserve its KE better....which actually, in some circumstances, can be a disadvantage but let's not digress....

    However, as I said before, the 230 gr. 45 ACP has higher sectional density than a 115 gr. 9 mm...so with everything else being equal (energy, bullet shape, etc...) the fortyfive slug will penetrate more....but it has nothing to do with its momentum....it's its energy by its sectional density.

    About the 9 mm ball being an overpenetrator.....is well known by everyone, I'm not pulling it out of my hat....

    If that 223 bullet moving at 1400 fps hits a vital area compared to a 9 mm round, yes it's going to be a better stopper....if expand or explode is going to create a larger wound channel.....

    And you did not tell me what is the SD of the 223 bullet.....a 40 gr?? a 55??? The higher the SD the higher the penetration

    You see...there are a lot of "IF" when it comes to stopping power.....


    So you still have to answer to my question: A 357 Mag is a more powerful round than a 45 ACP or not???


    Again, Kinetic energy = ability to do work...to expand and/or penetrate
     
    Last edited: Apr 23, 2009
  21. saturno_v

    saturno_v Member

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    Armed Bear.


    If a 200+ gr. 30-06 RN solid bullet hits your buffalo with more energy than a solid 45-70, it will outpenetrate the latter....and yes, it will create a narrower wound channel.
     
  22. chieftain

    chieftain Member

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    Dr Gary Roberts is the leading researcher into terminal ballistics in the United States today. It seems I have to put this data up a couple of times every week. Why? Because someone else has a Different X caliber vs. Y caliber question, or some variant on it.

    Fact is it’s about software, not hardware. The FBI use this mans research, and so do most of the LEO agencies in America, today.

    But if moving rubber blocks and bowling pins is the primary purpose of your pistol, get a 45acp. That is what I use at Bowling pin matches.

    I carry the caliber I have based on the platform/gun I am CCWing with. If a 1911 it will be in 45acp, if 9mm It will be a Highpower. Why? That is the calibers those guns were originally designed for. When I carried SIG’s it was in 9mm too.

    I have a lot of military combat experience, the two calibers I used were 45acp or 38spl. Didn't see a hill of beans between the two when push came to shove.

    If you want a good defense weapon, find reliability first, fit second, your ability to totally maintain it (take the factory armorer's course if need be), training and more training as much as you can afford, then “quality” practice. (the training and practice is a long term investment). Effective fighting with firearms IS A PERISHABLE SKILL.

    If caliber is still your question, you don’t really understand the problem.

    And with respect, your question is no different.

    Good luck

    Fred

    http://m4carbine.net/showthread.php?t=19887 From M4 Carbine.net.

     
  23. BlindJustice

    BlindJustice Member

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    Question for the O.P.

    what were the loads for the 9mm luger?
    seems the .45 was only GI Ball type?

    Typical cartridge discussion, nobody's
    opinion here has been changed much.

    and yes, I regularly shoot a
    .45 ACP - S&W 1911 & 625 as well
    as a 9mm Luger/CZ 75B.

    Bottom line tween the two for me, the 9mm LUger
    platform better carry twice the number of rounds

    Ychoice will probablyV

    Randall
     
  24. saturno_v

    saturno_v Member

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    An EXTREMELY informative article by Chuck Hawks about handgun stopping power

    http://www.chuckhawks.com/beginners_stopping_power.htm

    ======================================================

    Much of what one reads about the subject of handgun stopping power is a mixture of truth, half-truth, untruth, rumor and legend. A good place for inquiring minds to start would be to read the books by Ed Sanow and Evan Marshall, which are the most important works on the subject at the present time. They did the research, visited the morgues, talked to the shooting victims and police, and in the end collected the validated data from actual shootings that demonstrates what has worked in the real world. Their findings can correct a lot of popular misconceptions for those who are willing to learn.

    When discussing terminal ballistics what seems "reasonable" on the face of it often turns out not to be, sometimes for fairly complex reasons. One example would be the alleged superiority of the semi-wadcutter (SWC or "Keith style") bullet form. General Julian Hatcher, who invented the widely quoted (and copied) theory of Relative Stopping Power, and those who followed his lead theorized that such a bullet should be 25% more effective than the traditional Round Nose (RN) bullet. And, in fact, the SWC style bullet does look somehow deadlier than a RN bullet. Its sharp shouldered, truncated cone configuration was alleged to "chop" a chunk out of tissue and blood vessels as it passed through, rather than press them aside as it was alleged a RN bullet would do. This seemed to make sense to me, and for years I shot SWC style bullets. But when Sanow and Marshall evaluated over 100 actual shootings with 158 grain .38 Special lead SWC bullets, there proved to be no significant difference in stopping power compared to 158 grain .38 Special lead RN bullets at the same velocity. Clearly, the Hatcher theory has some flaws, no matter how reasonable it may seem.

    The stopping power of any handgun bullet turns out to be a function of its ability to disrupt vital bodily functions, not the diameter or weight or initial shape of the bullet that strikes the victim. For example, the difference in the size of the entrance hole made by a .451" bullet compared to that made by a .355" bullet in an elastic (semi-self sealing) material like skin turns out to be largely irrelevant to stopping power. The idea (which I have heard expressed) that a bigger bullet makes a bigger hole to "bleed out" a man or an animal is faintly ridiculous.

    The principle method of both stopping and killing with any firearm, whether rifle or pistol or shotgun, is the disruption of vital bodily functions. Fatally damage any animal's heart, liver, lungs, or central nervous system (including Homo sapiens) and it is not going to live long enough to bleed out. Fail to put your bullet in a vital spot and you are very likely to have a problem with a man or an animal. That is not to say that some bullet placements might not eventually cause death by loss of blood, or infection, or some other mechanism, but that is never the goal of any hunter OR gunfighter who wants an immediate one shot stop.

    Readers who have done some deer hunting have probably observed that often the entrance wound from a modern expanding rifle bullet (like a 100 grain .243, 130 grain .270, or 150 grain .308) seems minimal, with almost no external blood loss at all. In addition, there may be no exit wound--the bullet is often found just under the hide on the off side. But if the shot was true the deer's lungs probably look like they went through a blender, and the animal was down in seconds. That is an illustration of nearly perfect stopping power and it has little or nothing to do with the relatively small caliber of the bullet involved.

    Modern big bore advocates, following in the footsteps of Jeff Cooper (who I respect greatly and regard as a fine and very persuasive writer), will claim that the example cited in the paragraph above and witnessed by countless tens of thousands of deer hunters does not apply at typical handgun bullet impact velocities. They argue that below some magic impact velocity (usually about 2000 fps) the temporary stretch cavity that contributes so much to the lethality of rifle bullets like those in the example above ceases to exist. These writers continue to ignore any facts contrary to their preconceptions. (As an aside, it is interesting that big bore rifle fans use a similar argument, but for them the magic velocity is typically about 2400 fps.)

    Unfortunately, they are simply wrong about pistol and rifle terminal ballistics being fundamentally different, which can and has proven by controlled testing and high speed photography. In fact, they are fundamentally similar. Both depend on disrupting the function of vital organs, and bullets that reach such organs and expand quickly and violently, thus destroying a lot of tissue, are the best way to accomplish this, whether fired from a short barrel or a long one.

    How could the terminal ballistics of pistols and rifles be so different, since today we have pistols chambered for rifle cartridges and rifles chambered for pistol cartridges? In general, rifles have an advantage in kinetic energy, and this gives them an advantage in the amount of potential damage they can cause. (Of course, most of the big bore boys don't believe that kinetic energy matters, either, but that is their problem.)

    But in terms of the mechanisms of wound dynamics, rifle bullets and pistol bullets are both bullets, and function in pretty much the same way. The stopping power of pistol loads and the killing power of rifle loads are both based on a combination of the temporary stretch cavity and the permanent crush cavity produced by the bullet as it traverses the target. Any theory that ignores either of these factors will give erroneous results. Ignore the temporary stretch cavity and your results will favor big caliber bullets. Ignore the crush cavity and your results will favor high velocity, nearly explosive bullets. Both results will be incorrect.

    For at least 40 years I have been reading claims by various "authorities" that bullets cannot be made to expand reliably at typical handgun velocities. This is just plain not true. I discovered that in the middle 1960's by shooting game with .357 Magnum JHP expanding bullets, and it certainly isn't true now. These opinions usually trace their origin to ancient theories and flawed experiments, particularly the Thompson-LaGard study conducted around the turn of the (20th) Century and General Julian Hatcher's aforementioned Theory of Relative Stopping Power.

    When applied to contemporary handgun cartridges, theories based on Hatcher (which include Cooper's and Taylor's "Short Forms") have a statistical correlation to reality of only .64. In other words, they are meaningless. A vocal minority of gun writers and their disciples (again mostly big bore pistol fans) have come to accept this bunk as gospel, but it is really in the same category as urban legends. These "authorities" have been repeating this misinformation for as long as I can remember--but that does not make them right.

    It is instructive to read the actual results of the Thompson-LaGard cattle shooting experiments, which I have done. I urge my readers to do the same. It would be hard to imagine a less appropriate or more poorly controlled study. Despite the significance ascribed to it to this day by the ignorant and willfully blind, it proved absolutely nothing about the lethality or stopping power (on humans) of the handgun cartridges and loads tested. And it is even less relevant (if possible) to modern handgun ammunition, since no expanding bullets were tested.

    All that the Thompson-LaGard experiment really proved is that none of the handgun loads tested were effective at killing cattle. Most of the bovines those early experimenters shot had to be put down with a sledge hammer! The conclusion that the .45 caliber pistol was superior was forgone from the outset due to the bias of the testers, and it became their official conclusion despite a startling lack of data to support it. Interestingly, the only steer put down quickly with one shot was killed by a round from the high velocity 7.65mm (.30 caliber) Luger pistol!

    Well designed bullets (which includes most of the JHP pistol bullets now on the market) expand very reliably at their intended impact velocity. How do you imagine the 115 grain JHP 9x19 +P load, 125 grain JHP .357 load, 155 grain JHP .40 S&W load, and 230 grain JHP .45 ACP loads earned those outstanding 90%+ one shot stop records in the real world? In a sentence: due to the consistent performance of their JHP bullets.

    The famous 125 grain .357 JHP bullet, the most effective one shot stopper of all handgun loads, penetrates 13.25" in ordinance gelatin and produces a football shaped stretch cavity. This is how the very best bullets perform. And bullet performance has a great effect on stopping power.

    For example, the .40 S&W has higher one shot stop percentages in the real world than the 10mm Auto. Yet both use exactly the same caliber bullets, and the 10mm Lite load has exactly the same velocity as the .40 S&W. What gives?

    The difference is a function of the terminal performance of the bullets involved. The FBI adopted the 10mm Lite load and became the main driving force behind 10mm load development. The FBI protocol calls for more penetration, and therefore less expansion, than is desirable to maximize stopping power in most shooting situations. They are more concerned about shooting through car doors, barricades, and so forth than putting criminals down with one shot in the typical frontal shooting situation that homeowners and civilians are most likely to face. The FBI essentially wanted ammunition designed for extended gun battles with perps hiding behind cover, and that is what they got. But as a result most 10mm ammo has less actual stopping power than the lighter, faster expanding bullets used in the best .40 S&W loads.

    I wrote this article, not as a diatribe against big bore handguns (indeed, some of them--using JHP bullets--are near the top of the stopping power list), but because I have grown weary of hearing and reading the same old misinformation endlessly repeated. My opinion is no better than anyone else's unless it correlates with reality. Read the actual studies, not what others say about the studies, and decide for yourself. For those concerned with the problem, handgun stopping power is too important a subject to be left to urban legend.

    ======================================================

    And this about stopping power in general

    http://www.chuckhawks.com/rifle_killing_power.htm

    An excerpt

    =============================================================================================================================================

    Linear momentum

    Momentum is calculated differently from energy in that it is the product of mass and velocity--not the square of velocity. This slants the result in favor of heavy bullets, and makes momentum the darling of the big bore crowd. Momentum is what tends to keep a mass in motion moving, in accordance with one of Newton's physical laws. It is unclear how (or if) this relates to killing power.

    Momentum is not widely referred to in the world of ballistics (terminal or otherwise). The term "momentum" is not even included in the Glossary of Terms in the back of the Hodgdon, Hornady, Lyman, Nosler, or Speer reloading manuals that happen to be piled on my desk as I write these words. (I checked!) I am inclined to conclude that momentum is a sort of red herring, favored by gun writers from the big bore school because it gives credibility to their existing prejudices in favor of big bore rifles and heavy bullets.

    The term "pounds feet" invented, I believe, by Elmer Keith, is another favorite comparative tool of the big bore school of gun writers. Pounds feet is merely momentum divided by 7000 (the number of grains in a pound). The comparative result is the same as an ordinary calculation of momentum, but using the term pounds feet gives the result a sort of pseudo scientific ring, as the lay reader may easily confuse "pounds feet" with the legitimate scientific measurement "foot pounds."

    As we have already seen, large diameter bullets tend to create a wide wound channel, and bullets that are heavy for their caliber have good sectional density and tend to create deep wound channels other factors being equal. These are clear advantages of heavy, large bore bullets from the standpoint of killing power. However, I doubt that calculating bullet momentum per se contributes anything to our understanding of the subject. Ditto for pounds feet.

    Another of Sir Isaac Newton's physical laws states that for every action there is an equal and opposite reaction, calculated in terms of momentum. This would imply that, in terms of momentum, the recoiling rifle has more killing power than the bullet it fires, since its momentum is in fact the same as the total ejecta from the barrel (the bullet plus the powder gasses). It is true that big bore rifles kick like the devil, but I doubt that even the most fervent true believer wishes to defend momentum as an indication of killing power in that light, for if it were true they should all be dead.

    ====================================================================================================================================================
     
  25. GoodKat

    GoodKat Member

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    I hope you're using "theory" in a colloquial sense, a scientific theory has to be heavily supported and cannot be contradicted by any of the evidence. I doubt hydrostatic shock has been written about in any peer-reviewed scientific journals.
     
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