Calibrated Ballistics Turret is NOT Matching POI

Discussion in 'Long Range Hunting & Shooting' started by Ingwe, Aug 16, 2019.


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  1. Rflamm250

    Rflamm250 Well-Known Member

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    I like to keep things simple as possible. I refuse to use apps and calculators while on a hunt. Custom Turrets have there place and can be efficient if made correctly. That being said, I would not burn a turret until i have verified everything which for me would be many rounds fired in different conditions and distances. Kenton makes turrets with Mills or minutes and custom yardages all in one, which I would prefer. My advise is shoot and write everything it down on paper. Write down every thing from conditions to rest used what direction your shooting anything you can think. After a dozen or so trips out, if you see consistency in drops make a turret for it.
     
  2. cohunt

    cohunt Well-Known Member

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    If you do this, make sure you do your testing/marking at your intended hunting/shooting elevation and temperature.
    When environmental conditions change, your mv and drops will slightly change also. And I recommend using an angle modifying range finder that gives you an angle modified distance rather than a LOS distance.
     
    Ingwe, bigngreen and rfurman24 like this.
  3. rfurman24

    rfurman24 Well-Known Member

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    I am currently testing a rifle with custom turrets. It works great at the marked temp/elevation(pressure). Outside of that I would not dare take a long range shot at an animal. I can not tell others what to do but there will never be anything as accurate as dialing the scope in MIL or MOA based on a ballistic calculator's output that has been validated. Until something better comes along I will be using a Sig 2400 or BR2 with a Kestrel. You could get away with a cheaper range finder and an app or kestrel it just takes longer.
     
    Ingwe likes this.
  4. bigngreen

    bigngreen Well-Known Member

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    The easiest solution is not the best, unless you shooting the same elevation and all enviros are the same with a no wind condition as you hunt, taking direct numbers will put you of again.
    Taking a quality app like AB and a quality BC then imputing all your data accurately with speed from a quality crony will get you a LONG ways. Verify your zero hight at 300 yards, I use a micrometer here and I run my 100 yard zero hight to put me dead on at my three hundred yards dial up. Then 600 yards and 1000 yards and at 1000 you my have to make a slight tune to velocity, this will take out turret and velocity error. Once you have your ballistics ironed out in a quality app you can then trust it to make turret making decisions for your hunting elevation and temps. The speed and ease of a BDC turret is AFTER set up.
    I typically have about a 3000 ft elevation change and see 40 degree temp swings, so I set up my turret at 7500 ft and 30 degree temp, I won't be able to get a click of difference the entire hunting season to 600 with that set up, I always dial a real-time solution if I have the time or the situation dictates so in the end the turret is also a backup plan for a ballistic solution.
     
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  5. vanders

    vanders Well-Known Member

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    So your time and money isn't completely wasted zero at 75 yards and not 100 and you might find your turret to be a lot closer. You may be a little low up close but not so high far out. A 18 inch deer target or 30 inch elk target you may hit just fine. Shoot your 1000 on flat ground and you may be surprised. If you are in the Utah area l would be glad to help you.
     
    Ingwe likes this.
  6. dougduey

    dougduey Well-Known Member

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    So, an update on why the BC for the 6.5 Bergers 140 gr VLD was so off.
    I had my follow up long range shooting class today. It was the field course, in which I was shooting from all sorts of improvised positions (450-1079 yards). The adjusted BC for the Berger was spot on today. After we finished with the field course, the instructor said he wanted to do a tracking test on a tall target to see if my scope was the issue and not the bullet BC. He shot a group at exactly 100 yards, then dialed up 20 moa and shot another group. Then he grabbed the target and measured the distance between the 2 groups. It should have been 20” but it was 21.25”!! That’s a 6% error. When we plugged the data into the ballistics calculator to adjust for the error and put the BC back to what it says on the Berger bullet box, it all lined up. I shot targets out past 700 yards to validate everything, and it was dead on.
    If I never shot this rifle past 500 yards, I honestly would have never known I had an issue. I’m glad my instructor had a hunch and decided to see if it was the issue.
    Now I have to contact Zeiss and see how they’re going to handle it. This is one of the new Zeiss V6 5-30x models. I love the glass on it, so I hope they’re customer service is good. So much for using this rifle on a NM pronghorn hunt this coming weekend. Luckily I have other rifles that want to go hunting!!
     
    RockyMtnMT likes this.
  7. I’m hugely against ballistic
    Turrets and/or reticles. Unless you always live at say, 500ft 68 deg f where it never changes more than 10 degrees with little density altitude variation, and always shoot in those environmental conditions with the exact same ammo. Winter makes ballistic turrets worthless other than a reference point as does changing ammo and even ammo lot numbers.
     
  8. djfriesen

    djfriesen Well-Known Member

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    Assuming the calibration is accurate (seems you verified it to 700 yds, correct?), why wouldn't you go hunting with it and then address CS issues during the off season?
     
  9. dougduey

    dougduey Well-Known Member

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    Because my 7 STW is dead on out to 1000 yards and I won’t have the slightest bit of doubt with it. It’s all about confidence right now. I’ll get the 6.5 taken care of. The gun is a shooter, just need the scope to be up to the task
     
  10. sedancowboy

    sedancowboy Well-Known Member

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    Dougduey For reference 20 moa is 20.94" each moa is 1.047" So you scope may not be off near as bad as you think. Before you send it back I would investigate further.
     
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  11. John Klingenberg

    John Klingenberg Well-Known Member

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    Nov 13, 2018
    Theres one cool trick i learned on STRELOCK PRO. If they have your bdc reticle in the library just put your load data in and it will mark the actual impact sistance at that hash mark. So as an example at the 400 yds hash i need to use it for 375 yard targets. Pretty handy data set and really represents field shooting better to me. Screenshot_20190821-014845_Strelok Pro.jpg on the reticle.
     
    Ingwe likes this.
  12. MarkA

    MarkA Well-Known Member

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    Dec 12, 2005
    NO.

    20 moa is 20 X 1.047 = 20.94 inches. Your scope is NOT the problem!
     
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  13. palerider3

    palerider3 Well-Known Member

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    I would have hoped his "Instructor" would have known this. But this seems to be pretty common with the people who think MOA is inches and mils are metric.
     
  14. dougduey

    dougduey Well-Known Member

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    Well I guess a former Marine Recon sniper for 14 years with multiple deployments doesn’t know what he’s talking about. I’m sure he dumbed it down for me and factored that in because we did talk about the exact measurement of 1 moa. He said it’s 1.25” higher than it should be. So, I’m sure I misspoke here