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Thread: Black Hills 77gr TMK 556 load

  1. #1
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    Black Hills 77gr TMK 556 load

    Black Hills sent me some ammo a while back to play with. And we're trying to piece a full review video together, but I uploaded a short 26 sec snip of the Chrono clip from today.

    This ammo cooks!

    https://www.youtube.com/watch?v=IEZ5kWegce4
    "What would a $2,000 Geissele Super Duty do that a $500 PSA door buster on Black Friday couldn't do?" - Stopsign32v

  2. #2
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    Quote Originally Posted by markm View Post
    Black Hills sent me some ammo a while back to play with. And we're trying to piece a full review video together, but I uploaded a short 26 sec snip of the Chrono clip from today. This ammo cooks!
    Were you using a bolt gun? What barrel length and chamber? What was the date on the headstamp of the cases?


    Black Hills now advertises that this load has a velocity of 2750 FPS from a 20” test barrel. I chronographed two different lots of the Black Hills 5.56mm 77 grain Tipped MatchKing from 2023 and one lot from ~2015. They were all fired from a Colt AR-15 with a chrome-lined, NATO chambered, 20” barrel with a 1:7” twist using 10-shot strings over the chronograph.





    The muzzle velocity that I obtained from the ~2015 lot of this ammunition was 2808 FPS with a standard deviation of 14 FPS with a coefficient of variation of 0.50%.





    The muzzle velocity for the first lot from 2023 was 2779 FPS with a standard deviation of 16 FPS. This lot had a coefficient of variation of 0.58%.
    The muzzle velocity for the second lot from 2023 was 2762 FPS with a standard deviation of 21 FPS and a coefficient of variation of 0.76%.


    Black Hills 5.56mm 77 Grain Tipped MatchKing Accuracy Evaluation Update





    In 2016 I posted an in-depth review of the Black Hills 5.56 77 grain Tipped MatchKing ammunition. Three 10-shot groups of that 2016 lot fired from an AR-15 with a Lothar Walther barrel had an average extreme spread of 1.26”. The smallest of those groups had an extreme spread of 1.14” with a mean radius of 0.39”.







    The cartridge overall length for the 2016 lot of the Black Hills 77 grain Tipped MatchKing averaged 2.246”, while the 2023 lot averaged 2.243”. The length of the bullet itself is basically the same for both lots. The 2016 lot was loaded in Winchester brass and the 2023 lot is loaded in Lake City brass with stab primer crimps. Both lots have sealant in the primer pockets and neither lot has sealant at the case mouth.



    In my 2016 review, I noted that the 77 grain Tipped MatchKing was one of the longest bullets being commercially loaded to magazine length in the 5.56mm cartridge and that it had such a long ogive that the cannelure extended past the bearing surface of the bullet and onto the ogive, giving the grooves of the cannelure a rather unique “arrowhead” appearance.











    The base to ogive measurement of the bullets in the 2023 lot is approximately 0.017” longer than the 2016 lot and the configuration of the bullet at the junction of the bearing surface and the ogive now allows for a full-fledged cannelure that does not appear to extend into the ogive, or it was just a matter of pressing the deep cannelure that makes it appear so.





    A 10-shot group of the 2023 lot of the Black Hills 5.56mm 77 grain Tipped MatchKing ammunition fired from the same Lothar Walther barreled AR-15 used to test the 2016 lot, fired under the same conditions from a distance of 100 yards had an extreme spread of 0.86” and a mean radius of 0.24”.






    …..
    Last edited by Molon; 03-30-24 at 20:02.
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    Sorry.. this was a clip from today for a full video to be finished later. Just impressed with the great velocity.

    20" 5R bolt gun with unknown chamber, but it's got a classic Remington Leade that doesn't act up with 556 ammo.

    We've actually shot the 77s to 1300 yards, but haven't documented the stuff good like we should.

    Also shot the 69 version BH sent me, and it was great too.
    "What would a $2,000 Geissele Super Duty do that a $500 PSA door buster on Black Friday couldn't do?" - Stopsign32v

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    Headstamps are 15 and 16. Not sure which bullet weight was which. Ususally the BH headstamps predate the actual lot number production date. At least in the Mil ammo we've received.
    "What would a $2,000 Geissele Super Duty do that a $500 PSA door buster on Black Friday couldn't do?" - Stopsign32v

  5. #5
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    What COAL are they loading the 77gr TMKs to?

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    Just opened a box and measured 2 rounds. 2.250" on the money. Both of them perfect.
    "What would a $2,000 Geissele Super Duty do that a $500 PSA door buster on Black Friday couldn't do?" - Stopsign32v

  7. #7
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    Quote Originally Posted by markm View Post
    Just opened a box and measured 2 rounds. 2.250" on the money. Both of them perfect.
    Thanks!

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