How to Shim Rifle Scope Rings!

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brihacharan
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How to Shim Rifle Scope Rings!

Post by brihacharan » Sat Apr 04, 2015 3:42 pm

How to Shim Rifle Scope Rings
Sometimes, for various reasons, a rifle scope reaches its maximum vertical adjustment before the rifle is sighted in on target. In many cases, you can circumvent this problem by purchasing different scope mounts or rings. Also, turn the elevation adjustment and count the clicks from one maximum upper to lower adjustment to make sure the reticles are properly centered across the adjustment spectrum. Shim a scope only as a last resort because it creates uneven torque on your scope that could damage it.

THINGS YOU'LL NEED
 Scope rings
 Scope mounts
 Aluminum can / 35 mm film
 File
 Drill / punch
 De-greasing spray
 Screwdriver
Image

INSTRUCTIONS
1. Determine where to shim the scope. If you need to lower the cross hairs, shim the front mount. If you need to raise the cross hairs, shim the rear mount.

2. Obtain shim material. It won’t take much thickness to achieve the desired elevation. Aluminum soda cans and 35 mm film work well.

3. Unscrew the appropriate mount from the rifle’s receiver. Always shim between the receiver and the scope mount base; never inside the scope rings.

4. Cut the shim material with scissors or metal shears to the same size as the scope mount base. File the edges on aluminum cans.

5. Drill or punch holes through the shim in alignment with the scope mount screw holes.

6. Spray the shim, the scope mount base and the rifle receiver with a de-greasing agent.

7. Place the shim on the receiver and attach the scope mount. Attach the scope inside the scope-mount rings.

8. Align the cross hairs on the target and determine whether the adjustment worked. If not, add another shim.
Briha

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aadhaulya
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Re: How to Shim Rifle Scope Rings!

Post by aadhaulya » Sat Apr 04, 2015 4:36 pm

Briha ji,

That is a good description of the solution.

Regards

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Basu
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Re: How to Shim Rifle Scope Rings!

Post by Basu » Sat Apr 04, 2015 5:01 pm

I have recently shimmed my scope.
My SDB45 was hitting 1.5" low at 10 mtrs after maximum adjustment.
As adviced by Sathya , I used 3 shims made from visiting card , and placed it below the rear ring.
The issue is sloved.
I think , 2 shims could have solved the issue also.

Basu
Not all those wander , are lost...............

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estousandy
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Re: How to Shim Rifle Scope Rings!

Post by estousandy » Sat Apr 04, 2015 8:11 pm

brihacharan wrote: 1. If you need to lower the cross hairs, shim the front mount. If you need to raise the cross hairs, shim the rear mount.

3. Unscrew the appropriate mount from the rifle’s receiver. Always shim between the receiver and the scope mount base; never inside the scope rings.

Briha
I had to shim my scope too while doing up the IHP35. It was hitting around 2" high at 10 mtrs after max clicks.

But i went with exactly the opposite ways than mentioned.

Image

Shimmed some 5 pieces of hard rexin table cover soaked in fevifit on the front ring lower & 1 piece on the rear ring upper. Came out exact & solid still at ~300 shots.

Briha, can you please clarify the "Always shim between the receiver and the scope mount base" part? In mine, the mount-rail bite has no give to make any adjustments at all . Also, shimming the rings came out well too.
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brihacharan
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Re: How to Shim Rifle Scope Rings!

Post by brihacharan » Tue Apr 07, 2015 4:20 pm

estousandy wrote: Briha, can you please clarify the "Always shim between the receiver and the scope mount base" part? In mine, the mount-rail bite has no give to make any adjustments at all . Also, shimming the rings came out well too.
Hi Sandip,
You're right in raising this query (y)
Its meant for receivers that have grooves cut into it for mounting scopes....
If you have a scope rail....then it would be the space between the top of the rail & scope mount....
Shimming is a tricky business....would prefer 35 mm camera film to visiting cards!
Briha
PS; Since a long time now...I use a one piece mount instead of the two piece....They hold the scope well...even accurate up-to 50 yds!!!

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