I recently bought a Leupold VX-R 3-9x40 CDS for my Winchester M70, just got my free dial back and installed it only find out that I am 11 clicks short of the 500yd mark. So apparently I need to either go and buy a 20 moa scope rail and another set of rings or shim my scope in my existing 30mm Talley rings. I would much prefer to shim as I really dont want to go spend another $200.00 for a setup that will for sure require me to modify my $800.00 McMillan stock to be able to see through the damn scope. Anybody on here ever run into this problem before ? How do you place the shims ? I understand that I can use pop cans to cut the shims from but but where do I put them ????
Shimming
- Thread starter Cole
- Start date
yes i just had this problem. for the short amount you are out, spend the 90 dollars and get burris 30mm Zee rings. they have adjustable shim packs that come with the rings. you can also rotate them to adjust for windage. this is how i fixed my issue. the problem with just shimming it, especially with a high quality scope, is that you can flex the scope body itself. and i dont know about you, but i dont want to damage a 500$ rifle scope to save 90 bucks. not sure where you're located but if youre in ontario, ellwood epps has them on the shelf.
edit : they are also like a round socket they sit in so if it wasnt enough and you wanted to add a bit of shim, they will allow the scope to sit on an even plane, where normal scope rings when torqued will press the scope flat onto the plane you have created for it.
edit : they are also like a round socket they sit in so if it wasnt enough and you wanted to add a bit of shim, they will allow the scope to sit on an even plane, where normal scope rings when torqued will press the scope flat onto the plane you have created for it.
I have bedded Talley rings to an action by shimming the rear ring up off the action and applying a small amout of Devcon to the front ring. Once that has set I bed the rear ring the same way. You'll need a lapping bar to clamp into the rings to keep them alinged while the bedding compound is setting up. It's a slow multi stage process but it works. For rings 4" apart it's roughly .001" of shim per MOA.
Careful with the shimming process, because depending on how you do it, you can set the rings "off square" in relation to the scope main tube and create sharp depression in your tube on one side of each ring effectively destroying your scope. The rings must be perfectly square to your scope tube, otherwise you're asking for trouble. I did shim the rear ring on CZ550 a few years back because of lack of 20 MOA rails on the market back then and I crushed the main tube and it was not even visible. I have been very careful with my scope mounting since and no longer do any Mickey Mousing.
Thank you, sir !!!
OP .... you may wish to read this reply from 84 Wankel again and, for all the reasons noted, buy the Burris Signature Zee rings .... ‘shimming’ is a VERY POOR option (if you are attempting to achieve the ability to zero at a longer range) when dealing with ‘standard’ ring/base sets as the process will place one ring on a higher ‘plane’ than the other which will - at the least - mar your scopes exterior finish as the ring sets clamp down on the tube. Try to visualize what is happening when you resort to a shim.
^^^ this
You can induce stress on your scope tube by shimming your bases. That's the bad news.
The good news is you are more likely to be relieving the stress on your scope by shimming; because the shims brought the base height back to where it was supposed to be in the first place. Receivers vary more than bases do.
A one piece base can be checked with an eye-ball gauge, looking for day-light. A two piece base set can be checked after they are installed with a straight edge across the tops and looking for daylight, or with the rings with a set of alignment bars. Scopes don't like going around corners.
The good news is you are more likely to be relieving the stress on your scope by shimming; because the shims brought the base height back to where it was supposed to be in the first place. Receivers vary more than bases do.
A one piece base can be checked with an eye-ball gauge, looking for day-light. A two piece base set can be checked after they are installed with a straight edge across the tops and looking for daylight, or with the rings with a set of alignment bars. Scopes don't like going around corners.
