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Need load data:SMK 77GR, 223cal for bolt action

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  • mrkurtz
    Member
    • Jan 2007
    • 174

    Need load data:SMK 77GR, 223cal for bolt action

    I have a bunch of Sierra match King bullets, 77 grains in 223 caliber. My problem is that Sierras reloading manual only covers loads for the AR 15 for that particular bullet. I intend to use Varget powder. The rifle is a Tikka super varmint bolt action. I was wondering if anyone had some accurate loads out there but I can safely use for a bolt action without running into over pressure problems.
    Thank you
  • #2
    divingin
    Veteran Member
    • Jul 2015
    • 2522

    Start low, work up to find where you're getting pressure signs. Just like with any other load. Plus, multiple references are always a good idea.

    As to a load, Hodgdon lists start at 21 gn (2528fps; 42,700CUP), and max at 23.7 gn (compressed load, 2737fps; 50,700CUP.) That's for the components you proposed: 77SMK, Varget. You can verify at Hodgdon.com, select Resources, then Reloading Data Center.

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    • #3
      highpower790
      Veteran Member
      • Jun 2013
      • 3481

      As suggested start low!I prefer 24.5,and net 2800fps at the muzzle from a 20" barrel.
      Keep it simple!

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      • #4
        hntnnut
        Senior Member
        • Jan 2008
        • 1066

        Theres a sticky above that's all about the 77smks.


        Richard
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        • #5
          ar15barrels
          I need a LIFE!!
          • Jan 2006
          • 56937

          Originally posted by mrkurtz
          I have a bunch of Sierra match King bullets, 77 grains in 223 caliber. My problem is that Sierras reloading manual only covers loads for the AR 15 for that particular bullet. I intend to use Varget powder. The rifle is a Tikka super varmint bolt action. I was wondering if anyone had some accurate loads out there but I can safely use for a bolt action without running into over pressure problems.
          Thank you
          Bolt actions often have chambers and magazines long enough for a 2.5" OAL.
          At 2.5" OAL, you can run more powder because you have more room.
          My load for 75 Amax at 2.480" is 23.5gr of Varget.

          Here is a quickload simulation with a 77gr SMK seated to 2.480" with Varget:

          Code:
          Cartridge          : .223 Rem. (SAAMI)
          Bullet             : .224, 77, Sierra HPBT MatchK 9377G G7
          Useable Case Capaci: 26.248 grain H2O = 1.704 cm³
          Cartridge O.A.L. L6: 2.480 inch = 62.99 mm
          Barrel Length      : 23.7 inch = 602.0 mm
          Powder             : Hodgdon VARGET
          
          Predicted data by increasing and decreasing the given charge,
          incremented in steps of 0.851% of nominal charge.
          CAUTION: Figures exceed maximum and minimum recommended loads !
          
          Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
           %       %    Grains   fps   ft.lbs    psi    psi      %        ms
          
          -08.5   92    21.50   2511    1078   38234   6509     92.7    1.315
          -07.7   93    21.70   2533    1097   39236   6576     93.1    1.299
          -06.8   94    21.90   2555    1116   40267   6641     93.5    1.284
          -06.0   94    22.10   2577    1136   41325   6706     93.9    1.269
          -05.1   95    22.30   2600    1155   42412   6770     94.2    1.255
          -04.3   96    22.50   2622    1175   43526   6832     94.6    1.240
          -03.4   97    22.70   2644    1195   44669   6894     94.9    1.226
          -02.6   98    22.90   2666    1215   45851   6954     95.3    1.212
          -01.7   99    23.10   2688    1236   47062   7012     95.6    1.198  ! Near Maximum !
          -00.9  100    23.30   2710    1256   48301   7070     95.9    1.185  ! Near Maximum !
          +00.0  100    23.50   2732    1276   49570   7126     96.2    1.171  ! Near Maximum !
          +00.9  101    23.70   2754    1297   50871   7181     96.5    1.158  ! Near Maximum !
          +01.7  102    23.90   2776    1318   52204   7234     96.8    1.145  ! Near Maximum !
          +02.6  103    24.10   2798    1339   53574   7286     97.1    1.133  ! Near Maximum !
          +03.4  104    24.30   2820    1360   54982   7336     97.3    1.120  !DANGEROUS LOAD-DO NOT USE!
          +04.3  105    24.50   2842    1381   56429   7385     97.6    1.107  !DANGEROUS LOAD-DO NOT USE!
          
          Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
          Data for burning rate increased by 10% relative to nominal value:
          +Ba    100    23.50   2860    1399   58406   7143     99.6    1.093  !DANGEROUS LOAD-DO NOT USE!
          Data for burning rate decreased by 10% relative to nominal value:
          -Ba    100    23.50   2568    1128   41015   6804     89.5    1.272
          Last edited by ar15barrels; 03-26-2020, 11:45 PM.
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