close
Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Hunting > Long Range Hunting & Shooting

Long Range Hunting & Shooting Nightforce Optics

Reply

Need a little technical help

LinkBack Thread Tools Display Modes
  #1  
Unread 10-10-2010, 07:19 PM
Silver Member
 
Join Date: Jun 2009
Location: Bedford PA
Posts: 286
Need a little technical help

Here's the scoop. I shoot every week past 1000 yards but lately I'm having a little trouble getting things figured out. Here's the situation I'm having.
I use the Nightforce software and put in the correct info concerning pressure, temp, altitude, scope height humidity and so on. My velocities were checked using 2 different chronographs (ced and pact) everything is entered right but when I shot at 1200 yards tonight my shot is consistantly 2 moa off. (high) This is happening every week and no matter how many times I double check things it's always off.
If you know a solution I'm all for it. I am using several different guns and get the same consistencies.
Thanks for any help, Dustin
__________________
My final authority in all matters of faith and practice is the King James Bible. It's still the monarch of books!!

Last edited by loosesniper2000; 10-11-2010 at 05:11 PM.
Reply With Quote
  •   #2  
    Unread 10-11-2010, 05:11 PM
    Silver Member
     
    Join Date: Jun 2009
    Location: Bedford PA
    Posts: 286
    Re: Need a little technical help

    Any suggestions?
    __________________
    My final authority in all matters of faith and practice is the King James Bible. It's still the monarch of books!!
    Reply With Quote

      #3  
    Unread 10-11-2010, 05:19 PM
    Silver Member
     
    Join Date: Nov 2009
    Location: Alaska
    Posts: 172
    Re: Need a little technical help

    Has it alway been 2moa off at that range? Maybe the bc isn't being calculated correctly in the ballistics program? Or even a lot change in your bullets?
    Reply With Quote
      #4  
    Unread 10-11-2010, 07:15 PM
    Gold Member
     
    Join Date: Sep 2009
    Location: SW MT or noVA
    Posts: 986
    Re: Need a little technical help

    are you adjusting for the magnus effect? are you also high at different yardages or only 1200? or is it less at shorter yardages?
    __________________
    "Out of range" is a theoretical concept as far as I'm concerned. Send it!
    Reply With Quote
      #5  
    Unread 10-11-2010, 08:32 PM
    Silver Member
     
    Join Date: Jun 2009
    Location: Bedford PA
    Posts: 286
    Re: Need a little technical help

    I adjusted for spin drift but the magnus effect I don't believe is on the software. If it is please let me know. As for the distance it's at other ranges as well. I would say it starts to differentiate about 800 yds.
    It's really bugging me I can't figure this thing out. I'll try another chronograph but I doubt that will help. I actually experimented with changing the B.C and it works out perfect. I know there's got to be something I'm missing. I know the magnus effect is a force perpendicular to the line of motion, but that usually equates to a horizontal drift.
    I appreciate the feedback, but still let me know where the option is to check this.
    Thanks
    __________________
    My final authority in all matters of faith and practice is the King James Bible. It's still the monarch of books!!
    Reply With Quote
      #6  
    Unread 10-11-2010, 09:02 PM
    Silver Member
     
    Join Date: Jun 2009
    Location: Bedford PA
    Posts: 286
    Re: Need a little technical help

    Quote:
    Originally Posted by partisan1911 View Post
    Has it alway been 2moa off at that range? Maybe the bc isn't being calculated correctly in the ballistics program? Or even a lot change in your bullets?
    I'm using the JLK 7mm vld bullets in one of my STW's They said the bc was .690 and I'm shooting at 1460 altitude. I really don't know how to tell if the bc is calculated correctly.
    I'd be fine if it was one bullet but I'm also experiencing it with 3 other guns
    __________________
    My final authority in all matters of faith and practice is the King James Bible. It's still the monarch of books!!
    Reply With Quote
      #7  
    Unread 10-11-2010, 09:21 PM
    Gold Member
     
    Join Date: Sep 2009
    Location: SW MT or noVA
    Posts: 986
    Re: Need a little technical help

    Magnus affect is about 15% of your windage. A right hand wind (assuming right hand twist bbl) means your bullet will impact high by around 15% of your windage (exact percentage varies with twist rate, muzzle velocity and a lot of others but 15% should get you very, very close).

    If you have a predominant right hand wind, that would explain why you shots are. However 2mins is a lot, you would have to have dialed a LOT of windage

    also, what is the terrain like? You could very well be shooting through an upwards wind. That would raise impact.
    __________________
    "Out of range" is a theoretical concept as far as I'm concerned. Send it!
    Reply With Quote
    Reply

    Bookmarks

    Thread Tools
    Display Modes


    Similar Threads for: Need a little technical help
    Thread Thread Starter Forum Replies Last Post
    We need a technical article to be written on.... Len Backus General Discussion 3 10-14-2011 02:38 AM
    375 6 pointer at 636 yds, 30-378, technical LR3 Rifles, Bullets, Barrels & Ballistics 7 11-03-2009 10:26 PM
    Technical mil /reticle ranging ? sscoyote Long Range Scopes and Other Optics 7 06-24-2005 06:28 PM
    getting too technical 10X General Discussion 6 09-12-2004 04:40 PM
    Technical question Long Range Hunting & Shooting 25 01-03-2004 10:57 AM


    All times are GMT -5. The time now is 06:46 AM.


    Powered by vBulletin ©2000 - 2017, Jelsoft Enterprises Ltd.
    Content Management Powered by vBadvanced CMPS
    All content ©2010-2015 Long Range Hunting, LLC