Scope shim?

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1066
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Re: Scope shim?

#11 Post by 1066 »

Raise the rear of the scope for more elevation.

Shooting something like a .308 at more than 7-800 yards many scopes will run out of elevation, so often a 20 moa sight rail is fitted, this raises the rear of the scope to give another 20 moa of adjustment to the scope.

In your case, I personally wouldn't shim the scope - OK for a bodge job and common with airgun shooters but with quality equipment, there are better ways.

With good quality mounts they should be exactly in line, in fact you can get a tool to lap them exactly in line before fitting the scope, this means there is no torque or strain placed on the scope body when they are tightened.
Now, if you were to shim the rear, even 25 thou and tighten the mounts, you are actually bending the scope body.

An easy fix for this would be to use Burris mounts with plastic off-set inserts - they hold the scope well with no damage and the inserts can be adjusted to allow you to zero while keeping the scope optically centred.

http://opticswarehouse.co.uk/product/bu ... 30mm-34mm/
TARGETMASTER
an altogether better trickler
www.targetmasteruk.com
Kungfugerbil

Re: Scope shim?

#12 Post by Kungfugerbil »

^ Thank you - that's helpful. I suspect those rings might be a good solution - I only threw the scope on using some existing Hawke rings for a proof of concept.

Looking at the scope specs, it has a total elevation adjustment of 40MOA - presumably 20 up, 20 down. This means I need a 20MOA offset and the Burris rings offer that.

I wasn't aware of them - cheers for the heads up.
Kungfugerbil

Re: Scope shim?

#13 Post by Kungfugerbil »

Just doing some googling, and another suggestion is a 20MOA rail - I would obviously have to then buy new rings as well, but which would be the 'better' solution?

https://www.alanrhone-store.com/product ... ts_id=1451
1066
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Re: Scope shim?

#14 Post by 1066 »

I would go with the Burris rings, they're so versatile. I have them in 1" and 30mm. The 1" size have more options on the inserts. I believe they are 0,5,10,15, and 20, but the 30mm just have 0, 10 and 20.

I use them on my 6.5x284 and 6mmbr.(in combination with a 20moa rail) They never slip or mark the scope and the inserts can be fitted side to side to correct any windage alignment problems or up/down for extra elevation or a combination of the two.
TARGETMASTER
an altogether better trickler
www.targetmasteruk.com
1066
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Re: Scope shim?

#15 Post by 1066 »

Ahh! Just had a quick look at that rail. I see you have 11mm dovetail on your rifle.
I doubt that Burris do rings to fit an 11mm, this size is mostly air rifle and European rimfire. Using the 20moa rail will convert you 11mm dovetail into a weaver/picatinny size rail, then any standard rings will do.
TARGETMASTER
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Re: Scope shim?

#16 Post by TattooedGun »

1066 wrote:Ahh! Just had a quick look at that rail. I see you have 11mm dovetail on your rifle.
I doubt that Burris do rings to fit an 11mm, this size is mostly air rifle and European rimfire. Using the 20moa rail will convert you 11mm dovetail into a weaver/picatinny size rail, then any standard rings will do.
I would do this. Far more ring options for standard weaver/picatinny rails.
Kungfugerbil

Re: Scope shim?

#17 Post by Kungfugerbil »

Darn it. I got so excited at the solution I failed to examine the specifics :)

They actually do signature rings in rimfire dovetail, but only for 1" tube not the 30mm.

I think a rail is on the cards then...

Thanks for your input :)
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