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Thread: sunday buck.

  1. #1

    sunday buck.

    Sunday morning I took an eight point buck with Hornady 123 gr. AMAX.

    This is the 2nd deer I've taken this year with this cartridge. Each time, the deer have been DRT and the I've gotten complete pass through of the projectile with barely discernible entrance wounds. Exit wounds have been 6.5 caliber holes.

    Both kills were above or about the shoulders so I'm curious why the round is knocking 'em down instantly, even though I'm not seeing large tissue damage?

    Not that I'm complaining, much the opposite. I'm thrilled I get so much usable meat. I'm just curious why its working so well.

  2. #2
    High shoulder shoot puts them down quick.

  3. #3
    Warrior
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    Are you clipping the back bone, that will drop them like a rock. Sometimes you hit rib close enough to the backbone and deliver enough shock to drop them then secondary projectiles from the bullet coming apart kills them before the recover from the shock

  4. #4
    Super Moderator LRRPF52's Avatar
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    What distance and what barrel length?

    Have you chronographed that round in your rifle?

    123g AMAX has pretty rapid expansion, good weight retention, and deep penetration.

    Twist rate also seems to be an overlooked factor all these years.

    Have you updated the Game Knock-Down Survey?
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  5. #5
    Quote Originally Posted by LRRPF52 View Post
    What distance and what barrel length?

    Have you chronographed that round in your rifle?

    123g AMAX has pretty rapid expansion, good weight retention, and deep penetration.

    Twist rate also seems to be an overlooked factor all these years.

    Have you updated the Game Knock-Down Survey?
    Distance was 80-ish yrds. with a 20" 1/8 twist saturn barrel.

    No haven't chronographed the round, its Hornady though so the data is out there.

    I saw very little wound effects, to be honest. And the exit wound was just a bullet hole.
    One thing I failed to mention in my initial post was that as I was gut piling him I literally had to do it purely by feel in his upper cavitiy because they was so much blood my hands were fully immersed in it.

    From that I know I hit something important, but not his heart, it was untouched. I did not fully examine his lungs. they seemed in good shape.

  6. #6
    Bloodstained
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    You hit the Vagus Nerve Bundle located above the heart. It is a cockroach shot. Lights out but can mess up the tenderloins if it hits to far back.

  7. #7
    Twist rate also seems to be an overlooked factor all these years.


    LR, can you elaborate on this a bit? This is the first time I've ever heard twist rate mentioned as a factor in knocking down game, and I'm intrigued.

  8. #8
    Super Moderator LRRPF52's Avatar
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    Quote Originally Posted by IescapedCali View Post
    Twist rate also seems to be an overlooked factor all these years.


    LR, can you elaborate on this a bit? This is the first time I've ever heard twist rate mentioned as a factor in knocking down game, and I'm intrigued.
    I always wondered about it because of shear force on the projectile should be theoretically greater with higher rpm vs lower.

    We were talking with Hornady's engineers at SHOT earlier this year, and they said they see more expansion at distance when shooting at 400yds in gel than if you were to download to test for impact velocity and terminal effects.

    When you download, you don't get the same rpm on impact and the results are noticeable enough to be repeatable when testing full power loads at 400yds.

    A projectile that has a longer shank and tail end will have conservation of angular momentum (energy retained in its spin axis) better than one with a shorter shank and tail, so my thinking before I consulted with Hornady was that long-for-caliber projectiles with fast rpm should have better penetration and better tissue disruption from mushroom, fragmenting, or peeling.

    It appears that Hornady's tests confirmed my suspicions. I had talked with JASmith about this over the years whenever we were discussing the Hornady HITS method, and other theoretical approaches to hunting terminal effects, because it has often been stated that 2 projectiles of different diameter will have the same performance after mushrooming if they impact at the same speed.

    That didn't seem right to me, since one projectile with a long shank and tail will have different levels of retained angular momentum when spun at higher rpm.
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  9. #9
    Thank you for that excellent explaination, complete with the back story. I've shot all my life, but until I found the Grendel, and this forum, I have never had this many experienced precision shooters in my sphere, and certainly have never had so many willing to share. Love this forum.

  10. #10
    Warrior rickOshay's Avatar
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    Quote Originally Posted by LRRPF52 View Post
    I always wondered about it because of shear force on the projectile should be theoretically greater with higher rpm vs lower.

    We were talking with Hornady's engineers at SHOT earlier this year, and they said they see more expansion at distance when shooting at 400yds in gel than if you were to download to test for impact velocity and terminal effects.

    When you download, you don't get the same rpm on impact and the results are noticeable enough to be repeatable when testing full power loads at 400yds.
    Not sure I understand your thought process. Are you saying that a bullet will penetrate better at distance due to higher spin rate down range?

    Your quote from Hornady is about expansion, not penetration. As we know, bullet penetration is U-shaped: greater penetration at low and high speeds, less at moderate speed. Greater expansion at the same impact speed would result in less penetration, not more.

    Once the bullet leaves the barrel, both velocity and spin will decay with time/distance due to friction. So the greatest spin rate is at the muzzle.

    Higher penetration down range may be due to bullet stabilization and therefore less yaw, so the bullet impacts at less of an angle. Longer bullets will benefit from greater stability and more likely to hit closer to the tip. Shorter, less stable bullets will impact at a slight angle, penetrating less.

    Greater expansion down range is likely due to the slight separation of the jacket from the lead core as a result of heat and centrifugal force. The more stable the bullet, the greater cumulative effects of both due to higher retained velocity and spin. This effect would be missed when downloading.

    I'm not an engineer, so am I missing something?

  11. #11
    Super Moderator LRRPF52's Avatar
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    The rpm doesn't deteriorate enough within fractions of a second of flight time, so they see more expansion at 400yds than they do at close range with downloaded ammo to simulate 400yd impact speed.
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  12. #12
    New to the Forum ... glad to be here!

    A few years back, I remember reading of a gent who shared spying an article on DRT in African game animals. As I recall, a vet did necropsies on animals taken in herd-culling operations. What they found in the DRT carcasses was what amounted to a MASSIVE overload of the blood system depending on where the heart was in its rhythm when the shot struck. In effect, it's like a giant stroke that overloads the brain ... a fatal cerebral vascular accident (CVA) in medical terms. The animal (in effect) strokes out, with instantaneous or near-instantaneous incapacitation.

    This effect certainly could be tagged as one reason for DRT. It also may explain why the same shot in the same place sees the animal go running off, only to expire after some distance is covered -- the heart was in a different phase of its rhythm.

  13. #13
    Yep, found the article at Outdoor Life ... it was a Cape Buffalo culling operation ... here's the link: https://www.outdoorlife.com/articles...m-flatten-game

    Scroll down to the section with the subhead: New Evidence.

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