100 yard zero changing

Discussion in 'Long Range Hunting & Shooting' started by arrow, Jan 31, 2013.

  1. arrow

    arrow Well-Known Member

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    Whenever I go shooting I always start at 100 yards to check my zero. It usually take 1/4 Moa or so in some direction to get it on. The atmospherics are the same plus or minus 10 degrees or so an this is non clean cold bore shooting. I will do nothing to my rifle when I am done shooting, go back next weekend and it is off again. I handle it carefully and it is a leupold mark 4 with badger rings/ base. So I don't think anything is shifting on me. I make sure there is no parallax before I start. Also using the same lot of components. I have noticed it with me with other rifles as well as other people going through the same thing. Anyone else have this problem? What can cause this?
     
  2. arrow

    arrow Well-Known Member

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    Also it i am firing from the prone off bipods.
     

  3. BrentM

    BrentM Well-Known Member

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    So at @ 100 how tight is the grouping? When it is off by .25 moa, is it vertical or horizontal.

    If the scope is good, bases etc are tight, and the lug screws torqued properly then my guess is scope to shooter eye alignment is the issue. Your cheek is not lining up exactly the same place and your eye aligment is off. This is not uncommon.
     
  4. MTBULLET

    MTBULLET Well-Known Member

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    practice shooter positioning, make SURE it's the same each and every time.