Hornady 178 BTHP

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by RFtinkerer, May 23, 2012.

  1. RFtinkerer

    RFtinkerer Well-Known Member

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    Jun 7, 2011
    I'm just starting out in long range shooting, but I know enough that the listed 0.53 G1 BC isn't enough for the Hornady 178 BTHP. Or even realistic. I have a site that I will be able to get a 1100 yard shot soon, and I would like to make a first round hit if possible with the Hornady Superformance ammo. I am doing my own spotting, and it might be hard to see where I am landing. Has anyone characterized the Hornady 178 BTHP for either a stepped G1 BC or preferably G7? Also, would any other loaded factory ammo be better for this (308 Winchester)? I am not reloading yet. Thanks.
     
  2. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

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    Actually Hornady's advertised BC is only about 5% higher than I measured:

    My test results:
    G1 BC: .502 (average from 3000 to 1500 fps)
    G7 BC: .257 (valid for full supersonic range)

    It's typical for advertised BC's to be about 5% high and it's not necessarily 'inflation'. Some companies test their BC's over shorter ranges, like 300 yards, so the G1 BC is skewed toward the higher speed value which is a higher BC. Since I publish average BC's from 3000 to 1500 fps, they tend to be lower than the high speed BC's, but more accurate/useful for long range shooting.

    Of course this problem is much less of a problem with BC's referenced to the G7 standard because there is much less velocity dependence with G7 BC's.

    -Bryan
     

  3. RFtinkerer

    RFtinkerer Well-Known Member

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    Jun 7, 2011
    Great, thanks! Looks like I'm pushing the edge of my supersonic range with a 308. That'll satisfy me. Guess it's on to a 338 Lapua from here. :rolleyes: