Out of scope adjustment

Discussion in 'Gunsmithing' started by gedsar, Aug 30, 2008.

  1. gedsar

    gedsar Well-Known Member

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    Hi Guys,
    Just got my 7mm SAUM back from the smith. First shot at 25yds was 12in low, wind it up 48in go back to 100 and now is about 2in low so go to wind up and thats all she's got. The rifle was supposed to be fitted with a +20moa rail, its got one on there not sure if its + or not. I was more worried about getting it low enough not high enough. This is the first rail I've had. All my other rifles have ended up roughly in the middle of the range when sighted never run out before. Any ideas how to fix this or what may be wrong.
     
  2. tony stark

    tony stark Member

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    i guess that the first thing to do is to figure out what you have now.
    are there any manufactures markings on the rail?

    ask the guy that put it together.
     

  3. gedsar

    gedsar Well-Known Member

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    Cant get onto him, no markings at all on it.
     
  4. gedsar

    gedsar Well-Known Member

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    Ok, just set it up in the lathe and run a dial along the rail. The front is 10thou higher than the back. So next Q is how much shim do I need to put under the back to get it right, until I get the right rail sent up.

    The scope (burris FF11 tact 4.5 -14) has 40 moa adjustment. It is full up and 2moa low, so if I put 30thou under the back does this sound right?
     
  5. Varmint Hunter

    Varmint Hunter Well-Known Member

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    Nothing sounds right.

    The front of your scope base should be lower than the rear. Normally, you can see the taper in a 20moa base. It sounds like something is really out of kilter here. Your smith should have noticed this. I'd bring the rifle back to determine what the problem is. Maybe it is a mis-manufactured base but I wouldn't resolve this by shimming the base.

    Just my 2 cents
     
  6. gedsar

    gedsar Well-Known Member

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    Yeah I know, I am just looking to shim it to get it shooting for a week long hunt in 10days. It will defianately be getting fixed properly after it.
     
  7. dogdinger

    dogdinger Writers Guild

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    sounds like he put it on backwards to me....front should be low
     
  8. fireball10x

    fireball10x Member

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    Sounds like it's on backwards to me,flip it around, the front should be smaller than the back.
     
  9. gedsar

    gedsar Well-Known Member

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    It's on a model 7 action it can only go one way. Can anyone tell me the right amount of shimming?.
     
  10. tony stark

    tony stark Member

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    maybe he put it on backwards, if it's that simple, easy fix!
    if there are no markings on the base at all then i guess it could get put on wrong.
    super last resort, how about the burris rings with the inserts
     
  11. tony stark

    tony stark Member

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    sorry, didn't read the rest of the post