7mm 197g SMK

Discussion in 'Big Stuff -- 6.5mm, 7mm, 30 Cal' started by kyreloader, Aug 25, 2017.

  1. kyreloader

    kyreloader Gold $$ Contributor

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    I am running 255 in the straight 284 Win.
     
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  2. Ackley Kid

    Ackley Kid

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    Thank you kyreloader , what kind of velocity do you get from 284 before you see pressure ?
     
  3. kyreloader

    kyreloader Gold $$ Contributor

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    AK,

    Too early to tell to me honest. I only have 34 rounds down this new barrel (Krieger 1:8 twist). I have gone up to 54.9g of RL26 for 2730 fps without pressure. I have a ladder loaded with H4831SC, but presume it will be much slower. Concerned that if this barrel speeds up like most, I will be closer to 2800 fps with same load. Quickload predicted max powder load based on my current Fclass load is max of 55g at 61K with RL26.

    The barrel is still slow though, I shot my 180g load with H4350 that I shoot in my current Fclass rifle (30", 1:9 Brux) that averages 2820 fps and this barrel with the same load averaged 2755 fps (51.1g). (Distance to lands is the same in both rifles).

    If I can get a good load at 2700 fps with the 197s, the ballistics of this bullet is better than my current load of pointed Berger Hybrids at 2820 fps (only by 1 inch of wind at 1000 yards in 10 mph wind). Could really argue that the difference is not big enough to be chasing it, but I just think of all of the barely 4s (9s in US) that I had in Canada at the FC Worlds. I was 5 points out of 20th place during the Worlds and wonder how many of those I could have saved with 1 inch.

    Sorry to derail your question.
     
  4. Joe R

    Joe R Gold $$ Contributor

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    This?


    Capture 1.JPG
     
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