Shim Scope?

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njjessee
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Shim Scope?

Post by njjessee »

Hey everyone - I'm new to this sport and looking for some advice. Just finished installing a Timney trigger on my CZ 452 American (really like it, pain to inlet the stock but nice creep free trigger set to break at just over 2 lbs) and now I'm setting up the scope. Should I shim the scope? Using Burris steel rings (high).

Thanks,

Noah
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Innocent
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Re: Shim Scope?

Post by Innocent »

Noah,
There will be as many opinions as people on this site to answer that question. Shimming the scope will not hurt it, but I would recommend you try it wihtout shimming first.

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BCloninger
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Re: Shim Scope?

Post by BCloninger »

Burris signature Zee rings with their offset inserts work well on Weaver mounts, the kind with cross slots, but your CZ needs uses grooved mounts that work with BKL rings. If your scope readily handles the elevation without shims, I'm with Mary on this one. Only use them if you need them.
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Jason
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Re: Shim Scope?

Post by Jason »

If you've got the weight to spare, you can use the Burris Signature rimfire rings. They'll clamp directly to the dovetail on the gun. They weigh about 5oz between the two of them, though. They're beefy steel things.
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Bob259
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Re: Shim Scope?

Post by Bob259 »

If you need or want to shim.. 2 thickness's of your favorite soda or adult beverage can under the rear of the scope in the rear mount works well.
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Re: Shim Scope?

Post by Chattcatdaddy »

Bob259 wrote:If you need or want to shim.. 2 thickness's of your favorite soda or adult beverage can under the rear of the scope in the rear mount works well.
Yeah! what Bob said works just fine. Although I have used plastic from soda bottle as well.
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AZRifle
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Re: Shim Scope?

Post by AZRifle »

My 2-cents (well maybe 4) for what it is worth...

If you decide NOT to shim. The very least you should do is verify how much more upward adjustment at the Rams you have left. If it is minimal, you may end up remounting your scope with shims anyway because you wanted to use different ammunition.

Personally, I would not mount a scope without shims. Physically they are not an issue being there when the scope is properly mounted. On the technical aspect, they are used to help keep the upward and downward adjustment levels of your scope centered. I don't even like the thought of having my Ram adjustment near the maximum of my scopes capabilities. When you decide you need to adjust up in a match, and it does not work properly, there is not going to be some warning about it. Most often the knob turns but nothing happens and, you continue to shoot low.

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Re: Shim Scope?

Post by Jerry G »

Chicken zero should be a little below center of your scope. If you shim, go with the two thickness of an alum beer can. Make sure they are centered in the bottom of your back ring.
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Trent
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Re: Shim Scope?

Post by Trent »

And for gods sake don't use crappy beer cans. Buy the good stuff! :D :D
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Re: Shim Scope?

Post by njjessee »

Thanks for the input everyone. Curious.. doesn't shimming place stresses on the scope tube that just might not be good for it?

Noah
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Re: Shim Scope?

Post by AZRifle »

I have swapped scopes back and forth quite a few times. I have never noticed any damage to the scope tubes. I do not measure the force I put on the screws but I do tighten them fairly solid. I make sure it is not as tight as I can go either.

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Re: Shim Scope?

Post by Boyd L. »

Trent wrote:And for gods sake don't use crappy beer cans. Buy the good stuff! :D :D
What?!?!?!? I've never seen a "crappy" beer can. :-o
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Re: Shim Scope?

Post by Bob Mc Alice »

Some highpower shooters must also shim to reach 500 meters. Larger diameter slow moving heavy bullets fall rather fast out that far. I routinely put .010 to .014 thick brass shims under the back bases of my rifles. A typical 168 gr. 7mm ram load will barely reach with a Leupold 6.5-20x maxed out. The shimming will buy me an extra 50 to 60 inches or so of elevation to keep the reticle assembly more centered inside the tube. I have not experienced any problems with this little tube flexing in all the time I have done it.


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Re: Shim Scope?

Post by Jerry G »

To me, a crappy beer can is an empty beer can.
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Bob259
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Re: Shim Scope?

Post by Bob259 »

Looks like a Coors can to me McAlice ;)
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