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Should I pay attention to muzzle energy?

Discussion in 'Caliber Corner' started by KenB22, Dec 19, 2009.

  1. KenB22


    Jul 28, 2009
    I think I know the 5 most important things about any encounter with a BG are placement, placement, expansion, placement and expansion. That is assuming you use a caliber you can shoot well and practice, practice, practice. What I am wondering if muzzle energy is something I should consider assuming I use a round that meets or exceeds the FBI protocol. My thinking is that if I were in a fistfight with Mike Tyson, a blow to my head may well kill me. However, if he tapped me on the shoulder I'd be OK for a short while before I cried like a baby. If he really hit me on the shoulder, it may not kill me but it sure would make it hard for me to keep going in the short term. Is this analogous to muzzle energy. IF I ever had to draw, I'm interested in having my non-CNS hits be more like a punch, not a tap from Tyson. For example only, the muzzle energy for a 165 grain .40 round is greater than a 185 grain round. If I were to miss the CNS and hit someone with a 165 grain round, would that have more "punch" at the receiving end or are there just too many variables to make this a consideration. I am normally a fan of the heaviest round for a caliber but this has me possibly rethinking things if ME is a factor
  2. ajstrider

    ajstrider Silent Warrior

    Apr 17, 2005
    Western Kentucky
    If you start thinking about energy, there is a lot more you need to consider than just the numbers. How much of that energy is going to be transferred and how fast will be transferred are two other great questions. A over penetrating bullet that passes through a target won't transfer all of its energy because of course, it is still flying out the other side with some energy! The faster the bullet travels, the faster it should transfer energy, also, the larger the frontal section of the bullet, the faster it should deliver energy.

    It is one great big balance game and the choice of loads is a personal one.

  3. KenB22


    Jul 28, 2009
    Thanks. I think with modern JPH from reputable manufacturers like speer, federal etc. , I'm not worried about overpenetration. I am assuming all of the energy is deposited in the target and not passed through. I was wondering if the difference in ME from different rounds and different calibers could be felt by the BG when hit with a non-CNS strike. I know adrenaline does strange things too and that may also be a reason why this is unknowable. I am questioning myself if I should shoot the lightest bullet I can for each caliber assuming the round passes the FBI tests. I know there are many light and fast rounds that have enormous ME but they are off the table because many of them don't pass the FBI protocol. Should I just shoot the heaviest rounds I can and practice and quit this mental gymnastics over ME?
  4. JimBianchi

    JimBianchi Da Da CLM

    Feb 15, 2006
    Las Vegas
    If you look at the 12 to 14 inch FBI recommend penetration standard, and do the math on the individual rounds that meet the standard, you will see many 350-400FPE round do very well.

    BUT.... the all time one-stop champ (according to statistics) is still the 357MAG round doing 600-700FPE. I recently read the reason it was so effective has more to do with the fact for 10yrs there was no competition. Literally 90% departments in the US carried it for 10 or more years. As compared to now there are half a dozen great calibers, with the 40 leading the LE charge. Basically for ten years most bad guys were being killed with only one caliber. Those kind of numbers can skew the tally a bit. Also, Crime was at a near all time high when the 357 was carried extensively, as compared to now violent crime is at a near per capita low. (But the 24hr news cycle makes it seem worse than ever) Here is a link with an accurate graph.

    So energy is important, but as you know, shot placement is more important. Use one of the majors, with a modern bullet and practice practice practice.

    (I carry HST 147 in my Kahr MK9 and my G26. My G30 is loaded with 13rds of WIN ranger 230grn. When (rarely) carry my Ruger Vaquero 357MAG, it is WIN SilverTips. Just because I have a few boxes from back in the day...)
  5. vanilla_gorilla


    May 31, 2005
    To quote a wise man, "Penetration is king, expansion is queen, and everything else is angels dancing on the heads of pins."
  6. Welcome to GT. There is an awful lot of water over this dam here at GT. I know because I've read many and participated in a few of the threads. The real vets here with interesting and informed positions have already aired their experience and thinking on this subject so many times that they tire of the fight. So, try the search function--you'll find more interesting and entertaining reading than you can stand.
  7. IndyGunFreak


    Jan 26, 2001
    In my opinion, ME is pretty close to the most irrelevant figure there is for Self Defense ammo...

    Reason? Most of the really high muzzle energy producers, do not penetrate as well, due to the rapid energy dump. There are exceptions of course, the .357mag and the 10mm among them... however these rounds have a fair bit of thump to them. Using the 9mm as an example, a lot of the rounds with really high energy numbers, are the 115's. These bullets do not penetrate as well as the 124/147's, and in some cases have shown to fragment badly...

    Its all about what you value... Personally, I value Placement and Penetration over all other factors. If I can put the round where I want it, and it penetrates reasonably well, I don't care about ME, or to a lesser extent, expansion. The nice thing about a round that expands well, is there's a pretty good chance it is not going to over penetrate on the intended target and hit an innocent bystander.

  8. Brucev


    Jul 19, 2009
    100% agree!
  9. MSgt Dotson

    MSgt Dotson

    Sep 30, 2006
    ME will be higher with higher velocities (significantly so, do the (velocity x velocity) component in computing ME), but, this will not necessarily be significant in a personal defense round unless said energy/velocity results in increased expansion/penetration. Beyond a certain point, (approx 400-500 ft lbs), odds are that increasing the velocity even further merely results in an 'shoot thru'.

    Most 180 gr JHp rounds are preferred over 165 gr rounds for the .40, IMO...
  10. KenB22


    Jul 28, 2009
    Thanks to all. I'll stick to heavy for caliber for penetration assuming the round passses FBI recommendations.
  11. 481


    Feb 20, 2009
    I would encourage you to obtain and read, "Bullet Penetration: Modeling the Dynamics and Incapacitation Resulting from Wound Trauma" by Duncan MacPherson. It is hard to find, but well worth the effort to locate and will provide the insight necessary for making an informed decision on which ammunition to chose and to carry. MacPherson performed all of his own research, analyzed and interpreted the results and came up some authoritative mathematical models that redefine how bullet performance should be considered.

    It is a bit "heavy" on math (the Calculus) for those not so inclined, but it is also written so that you can "read through" those sections that are more than what you wanna deal with in the way of math and still get a good grasp of what MacPherson has to say on the matter.
  12. fredj338


    Dec 22, 2004
    The diff between the ME of either is less than what the variation from round to round would be in a box of given ammo. When you start doubleing energy, like 41mags, 44mags etc. w/ the right bullet selection, then ME starts to show up on your target.
  13. bfg1971


    Apr 19, 2003
    Ewa Beach, HI
    If the ammo already meets FBI specs then the only reason to consider muzzle energy would be if you were going to put your finger in front of the muzzle. :supergrin:

    My preferred round expands more than 2x original and penetrates about 16 inches. The muzzle energy was the last thing I looked at when deciding on my loading.
  14. PghJim


    Apr 21, 2005
    I will tell you this, with in the limitations of the settlement agreement. I was accidentaly shot with a 40 S&W 135 gr factory round rated at over 1300 fps. I think that carrys some energy, and according to charts is a pretty good stopper. When the gun went off, the bullet enter the left breast pocket of my sports jacket, and hit an expensive Parker pen in the inside pocket. The bullet bent the steel refill cartridge and angled down and enter my body just below my left lung. It damaged my large intestine and exited out the back with an exit wound the size of a quarter. Hear is the strange thing. I remember seeing and hearing the gun go off and thinking to myself how lucky I was that I was not hit. I did not feel a thing and it was not until I looked down at my shirt that I noticed blood. I felt no pain until I was in the Life Flight Helocopter.

    If there is one lessen I learned, is that shot placement is the most important thing
  15. JohnKSa


    Sep 8, 2000
    DFW Area, TX
    When comparing two generally similar loadings you can think of energy as being a measure of the potential of a particular loading to cause damage. Just keep in mind that there are a myriad of circumstances that can result in a round not living up to its potential. Poor placement and insufficient penetration are the two main flies in the ointment.

    Getting wrapped up in numerical attempts to quantify the overall performance of various loadings is unproductive if your motives are primarily practical. If you just want results, buy several types of premium self-defense loadings in a caliber that will reliably expand and penetrate at least 12". Then test them to see which one works best in your gun, is the most accurate and that you can shoot the best.

    Then find a practice round that duplicates the "feel" of your self-defense round and practice a lot.

    On the other hand, if you just like discussing the intricacies of projectile performance then that's a different story. :supergrin:
  16. KenB22


    Jul 28, 2009
    Thanks. Not into overthinking things if I can help it. I'll get McPherson's book and read it to educate myself. Then I'll pick a round my gun shoots well and practice to improve placement.

  17. It's not hard to find here:
  18. Snowman92D


    Oct 6, 2001
    Which "wise man" said that?
  19. mitchshrader

    mitchshrader Deceased

    Jun 14, 2005
    I don't have a clue what your research will illuminate, but I'll agree that heavy for caliber bullets make deeper holes. I want that result and intend to continue using said heavy bullets.

    I happen to believe they are usually more accurate as well, and I can't offer proof of that either.
  20. uz2bUSMC

    uz2bUSMC 10mm defender

    Oct 21, 2005
    J-Ville NC
    A one shot stop is a one shot stop.

    More shoots won't skew the numbers, it will give a more accurate representation of what the cartridge will do routinely. Being a great man stopper back then is the same as being a great manstopper today.