Penetration vs Expansion

Discussion in 'Glock Forum' started by djg1965, Sep 27, 2020.

  1. djg1965

    djg1965 Active Member

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    In a self defense situation, I think it's safe to say that penetration is desired over expansion. However, I wonder how many of us carry rounds based on expansion over penetration? This issue has probably been litigated to death before, but I couldn't find it in many forums.
     
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  2. LostinTexas

    LostinTexas Well-Known Member

    IIRC the "standard" is 1.5 times the unfired diameter for being satisfactory. Plenty exceed that.
    Usually big expansion means less penetration. The degree of that is the devil in the details.
    My opinion is I'd rather have an inch over maximum than an inch over minimum. Judging on all the folks I've picked up off the street and other places, that is my preference.
    I'd love to have a 9MM or 40 that expanded to an inch and hit 18 inches consistently, but that is not available just yet. The ammo I use in 40 hits the 15-16 in mark and expands well. The 9MM I landed on expands 1.5 times but hits the 19 inch mark consistently. Some believe that is too much, but they can use what they want.
    Cheers
     
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  3. Southlake

    Southlake Salt Life Staff Member Moderator Lifetime Supporting Member

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    Based on the name of this thread and being a conservative moderator, I was curious about the contents.
     
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  4. buddy157

    buddy157 Active Member

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    [​IMG]
     
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  5. Lucian_253

    Lucian_253 Well-Known Member Supporter

    I research my carry ammo for the best of both. I stay away for the light grain weight for caliber rounds, because they usually expand to quickly. The caliber I worried about the most was .380 acp. I know a lot of guys who carry fmj’s instead of hollow point ammo, for fear of HP’s under penetrating. So I’m my micro .380’s I carry underwood non plus P Xtreme defenders ( not penetrators).
     
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  6. goodguywithagun

    goodguywithagun Active Member

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    I carry Federal HST’s. I picked these out of the 4th gallon jug. These are 9mm.

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  7. LostinTexas

    LostinTexas Well-Known Member

    Water is a fun media, and can tell us a lot. A milk jug is 8 inches, so you got 24+ inches of penetration. Not likely in a live target or 10% ordinance gel.
    HST wouldn't be the scream it is, if that were the case.
     
  8. Lucian_253

    Lucian_253 Well-Known Member Supporter

    Can’t go wrong with HST’s!!
     
  9. Southlake

    Southlake Salt Life Staff Member Moderator Lifetime Supporting Member

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    Agreed
     
  10. djg1965

    djg1965 Active Member

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    Several months ago, while at my LGS they were all hyping the Liberty 50gr at 2000/fps. Obviously, I was impressed at how light the box was. I bought a box and carried it in my G48. I had concerns about a gun cycling this ammo but thought my Glock would be the best gun I own for that. I knew it wouldn't over penetrate, nor would it expand very well. Good carry for crowded venues?? I've since switched to one cartridge for all guns, Gold Dot 124gr +p.
     
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  11. NWG40

    NWG40 Well-Known Member Supporter

    Likewise as I do myself.
     
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  12. rbbeers

    rbbeers Well-Known Member Lifetime Supporting Member

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    AMMO REVIEW: 9mm Liberty Ultra Defense 50 gr JHP


    For what it's worth... :)

    Best regards,

    Bob
     
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  13. NWG40

    NWG40 Well-Known Member Supporter

    So it's dumping 400 ft. lb. of energy in the first 3 inches?
    That'll knock ya on your can alright. That's why I've gone to Underwood
    Extreme Defender ammo for my .380. Does the same thing.
     
  14. LostinTexas

    LostinTexas Well-Known Member

    flabbergasted.gif
     
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  15. rbbeers

    rbbeers Well-Known Member Lifetime Supporting Member

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    Really?!?! o_O

    Do you get 'knocked on your can' when you shoot a 9mm Luger pistol? :rolleyes:

    (I don't.) :D

    Best regards,

    Bob
     
    Last edited: Sep 28, 2020
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  16. Danzig

    Danzig I do hood rat sh%t! Supporter

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    Texas
  17. Southlake

    Southlake Salt Life Staff Member Moderator Lifetime Supporting Member

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  18. j102

    j102 Well-Known Member

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    That’s what I carry on my guns.
     
  19. j102

    j102 Well-Known Member

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    I think the intent of this thread is not to start an ammo war, but perhaps a discussion of what we consider more important between expansion and penetration. right?
    Aren’t we supposed to follow the FBI standards for a balance between the two?
     
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  20. rbbeers

    rbbeers Well-Known Member Lifetime Supporting Member

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    All major cartridge manufacturers do exactly that. Accordingly, they typically strive for the FBI's penetration mid-point of 15" (in ballistic gelatin with various barriers) and a minimum expansion of 1.5 times the bullet diameter.

    FBI Penetration Tests 1a.jpg
    Excerpted from: HORNADY’S CRITICAL DUTY AMMO
    https://public.ntoa.org/AppResources/publications/Articles/2158.pdf

    That said, in the real world, penetration without adequate expansion is preferred over expansion without adequate penetration simply because, to 'stop the threat', the bullet must typically disrupt vital functions... and, without adequate penetration (regardless of expansion), the probability of that happening decreases significantly.

    However, the goal of every manufacturer is to produce the 'perfect' cartridge as presented in HORNADY’S CRITICAL DUTY AMMO...

    "The “perfect round,” whether fired from a pistol or rifle, will always expand equally (as large as possible relative to caliber) every time it is fired into an opponent (bad guy). It will always penetrate to the desired depth of 12 to 18 inches. It will perform consistently shot to shot. This perfect round will bring on quick incapacitation by either disrupting the central nervous system or quickly lowering the blood pressure of the bad guy."
    And, to the best of my knowledge, they're all still working on 'perfection'. :rolleyes: :D

    Best regards,

    Bob
     
    Last edited: Sep 28, 2020
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