Shimming a scope question

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  • Fargo

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    In a state of acute Pork-i-docis
    I put a new scope on the old deer rifle to hopefully use it this year now that they are legal on private land. Rifle is a Ruger m77 in 270 which previously had a scope mounted on it with no issues. I went to sight it in last weekend and even with the windage maxed out, I am 4 inches right of POA at 50 yards.

    I do intend to swap out the rings at some point, but I'm not certain if I will be able to get a new set before deer season. Is there any reliable way to shim a scope in this circumstance? Disposable income is fleeting this time of year. Thanks in advance.
     

    biggen

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    If I remember correctly M77 rings are two different heights, yes? If they are the same height you could try switching the front to the back or flipping the rings.
     

    gregkl

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    I have used aluminum pop can pieces to shim scope mounts. Works well and if you cut the carefully you can't see them once done.
     

    BiscuitsandGravy

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    I would try 1- flip end to end 2- front turn-around, 3- rear turn-around if possible, 4- shim. I will say I don't know the m77 so its just a swag.

    I might be going by my local LGS Saturday and could see if they have some rings for it. They usually have a decent variety of accessories.

    :twocents:
     

    GREEN607

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    Apr 15, 2011
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    I put a new scope on the old deer rifle to hopefully use it this year now that they are legal on private land. Rifle is a Ruger m77 in 270 which previously had a scope mounted on it with no issues. I went to sight it in last weekend and even with the windage maxed out, I am 4 inches right of POA at 50 yards.

    I do intend to swap out the rings at some point, but I'm not certain if I will be able to get a new set before deer season. Is there any reliable way to shim a scope in this circumstance? Disposable income is fleeting this time of year. Thanks in advance.

    Doesn't the M77 have to use the special 'Ruger-type' rings?

    With the 'doublecatch' bottom, like this one?
    rug90279.jpg


    These are about $30 each, and SOLD INDIVIDUALLY.....
     
    Last edited:

    Tombs

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    I put a new scope on the old deer rifle to hopefully use it this year now that they are legal on private land. Rifle is a Ruger m77 in 270 which previously had a scope mounted on it with no issues. I went to sight it in last weekend and even with the windage maxed out, I am 4 inches right of POA at 50 yards.

    I do intend to swap out the rings at some point, but I'm not certain if I will be able to get a new set before deer season. Is there any reliable way to shim a scope in this circumstance? Disposable income is fleeting this time of year. Thanks in advance.

    Not sure how well it'd work for a scope, but I keep extremely cheap feeler gauges around to make shims out of.

    They're usually pretty long and narrow so you could wrap them around something and trim them to fit. I'd opt for a softer metal like brass if you could as I think it'll have a tendency to stay put better than steel. Most the cheap ones are loaded with brass anyway.
     

    churchmouse

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    Not sure how well it'd work for a scope, but I keep extremely cheap feeler gauges around to make shims out of.

    They're usually pretty long and narrow so you could wrap them around something and trim them to fit. I'd opt for a softer metal like brass if you could as I think it'll have a tendency to stay put better than steel. Most the cheap ones are loaded with brass anyway.

    I have a motor/pump shim kit that I now use for this. Depending on my needs I can get several out of each shim in the kit.
     

    Fargo

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    In a state of acute Pork-i-docis
    The scope is a Bushnell banner, I may swap it onto a different rifle and see what happens. My M77 doesn't have the proprietary Ruger mounts, it is drilled and tapped for weaver bases. I don't think that I need different height rings like the factory Ruger ones because my elevation was dead on from the outset, it is just the windage that is messed up. I made a couple of shims out of aluminum from a pop can slid them in and tightened it back down. I will give it a try in the next few days if I can make it out to the range. I may also try switching the rings side to side as some suggested as that might help as well. Thanks so much for all the input.
     

    halfmileharry

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    The scope is a Bushnell banner, I may swap it onto a different rifle and see what happens. My M77 doesn't have the proprietary Ruger mounts, it is drilled and tapped for weaver bases. I don't think that I need different height rings like the factory Ruger ones because my elevation was dead on from the outset, it is just the windage that is messed up. I made a couple of shims out of aluminum from a pop can slid them in and tightened it back down. I will give it a try in the next few days if I can make it out to the range. I may also try switching the rings side to side as some suggested as that might help as well. Thanks so much for all the input.

    I'd be looking real strong at the scope being the issue.
    Try a different scope before you do anything else. Make sure you're using solid mounting hardware as well.
    Is the "drill and tap" for weaver mounting factory or did someone else do the machine work?
     
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