338 bullet BC results from Snipers Hide

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Varminator 911, Dec 19, 2011.

  1. Varminator 911

    Varminator 911 Well-Known Member

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    Will try to post results from the Hide. Berger 300 measured less BC than Berger advertized and only marginally better than 300 SMK. No idea how real the results are.


    http://freepdfhosting.com/4626d2127d.pdf
     
  2. highridge1

    highridge1 Well-Known Member

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    According to the testing everyone is wrong???
     

  3. jmason

    jmason Well-Known Member

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    can u post a link to the thread? there was a thread on this here but I believe it went cold. I am very anxious to see how noel's bullets did.
     
  4. Varminator 911

    Varminator 911 Well-Known Member

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  5. JeffVN

    JeffVN Well-Known Member

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    The results are real. I was one of the people down-range working the laptops for the chronograph during the test.

    Other than Doppler radar, this was the first test (that I am aware of) that simultaneously tested velocity for a projectile at the muzzle, then again at roughly 300-475, and then again at 1,000-1,175 yards. for each shot. The results for 10 shots for each projectile were recorded.

    Granted there are aspects of every test that can be done differently by the people running the test, and this was only the first on what we expect will be several demponstrations.

    Jeffvn
     
  6. Broz

    Broz Well-Known Member

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    Jeff, I have not had time to read the entire thread yet. But could you tell me , are the BC numbers an average of all readings from the muzzle to 1200 yards?

    Thanks

    Jeff
     
  7. Broz

    Broz Well-Known Member

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    Jeff, thanks for the call today, always a pleasure talking rifles and bullets with you.

    After we got off the phone I looked at my stepped BC's for the 300 Berges.

    In the testing you guys did you have the Bergers at a G7 of .389 to 1200 yards. My BC's start with the G7 BC of .419 and by 1710 yards I am at .380 with a few fluctuations below and above in between. I though it was interesting that my actual field drops fell in line with your test as well. But to get the short end below 1000 yards to match up I have to use .419 which I think is in line with what Bryam Litz found in his testing to 600 yrds.

    Thanks

    Jeff
     
  8. JeffVN

    JeffVN Well-Known Member

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    Broz

    Good to talk with you gain. BC's - an interesting subject. Glad your rifle is doing so well for you.

    I agree that stepped BC s may be the only method that can do what you are doing at the distances that you are doing it. Absent doppler range data, or many trips to teh range with these bullets and a chronograph that measure velocity at distance, I'm not sure how we come up with a single BC that accurately describes a bullet from muzzle to subsonic transition and beyond.

    I know at least one guy with the Kestrel with Atrag installed in it and another device that believes in combination they are incredible accurate on teh very long range side (beyond 2,000 yards) but, like yourself he has a ton of very long range experience and relies a bunch on his data book also.
    JeffVN
     
  9. Rocky Mountain

    Rocky Mountain Well-Known Member

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    There is alot of truth in the quote above and probably why the sniper hide guys came up with G7 .389 at 1200yds and Litz came up with G7 .419 at 600yds
     
  10. jmden

    jmden Well-Known Member

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    Broz,

    Would you mind telling us your G7 steps for the 300 Berger?

    I didn't realize you were stepping the G7. I thought you were stepping the G1 from reading earlier posts. I must've missed some posts somewhere.

    I'd been wondering if G7 steps would be needed for this bullet and others similar to it as bullets of this form factor are getting farther and farther removed from the form factor of the actual G7 model. So, at that point, we start to need to step G7, just like we step G1.

    Not too familiar with Shooter yet. It must allow stepped G7s?

    Thanks,

    Jon
     
  11. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

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    The currently assessed performance (BC's) for the Berger 300 grain Hybrid is derived from 1000 yard testing, not 600 yards. The originally assessed BC's for the Gen 1 version of this bullet were done at 600 and were inaccurate (something like .890/.450 G1/G7). Since then, I only test .338's at 1000 yards, and the current BC's have been measured repeatedly in several tests at 1000.
    Here is my full reply to the Snipers Hide thread regarding the test results:
     
  12. jmden

    jmden Well-Known Member

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    Bryan, Thanks for keeping us in the loop. It is appreciated and I hope you and Kns can get together and iron out what is going on such that you both get consistent results.

    Would you mind commenting on my post right above yours in this thread?
     
  13. BryanLitz

    BryanLitz <b>Official LRH Sponsor</b>

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    Jon,

    At the ranges we're talking about (1500+) and more importantly, at ranges where the bullet slows to transonic speeds (below about 1340 fps), the need to determine the 'custom drag' of a particular bullet becomes more important for accurate trajectory prediction.

    Shooter does allow for piece-wise defined BC's, both G1 and G7; as many as you care to input.

    There is another program (mobile app) currently under development that I'm more directly involved in. This 'Applied Ballistics' app will have the ability to use 'custom drag curves' for a number of long range bullets. These custom curves are in no way related to any 'G' standard, so BC's are out the window all together. Rather, these custom drag curves will represent the exact drag of each bullet at each and every speed.
    Furthermore, the Applied Ballistics app will allow the user to define and apply one of 3 modes of 'Ballistic Calibration' in which the user enters range/observed drop and the program adjusts either: MV, drag, or drop over the defined range so the solution is matched exactly to a users system. This is similar to the 'trajectory validation' feature of exbal, except it allows 3 different modes, and can handle up to 3 pairs of range/drop pairs.

    For shooting out to and even beyond 1000 yards, G7 BC's are plenty accurate enough to give reliable trajectories. However, at extended ranges where the bullet starts approaching and going thru transonic, custom curves and ballistic calibration will help improve the accuracy of trajectory predictions.

    This new app will be available by mid Jan (NRA SHOT Show) for android, with an iPhone version soon after, and eventually a windows mobile and blackberry versions are planned as well. The program will have many other new features but I'm only 'leaking' the ones relevant to this discussion for now.

    Take care,
    -Bryan
     
  14. jmden

    jmden Well-Known Member

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    Thanks, Bryan. We'll look forward to learning more about your new app. That sounds great!

    Just as well it's not out yet as I'm trying hold out for the next iphone. By then, there should be plenty of good info/reviews out there about the new app.