How much misalignment between scope rings is acceptable?

[Mauser fan]

I’m installing some Talley lightweight scope mounts onto my new Winchester model 70 featherweight and I’m concerned with the amount of misalignment I’m seeing. When I place alignment bars in the rings and torque everything to spec, I’m seeing a vertical offset of about .008”. They have good alignment in all other directions. I don’t know if this height difference is due to the rings or if the receiver has a height difference between the front and rear mount locations. Do you think this amount of offset would put excessive stress on a scope or is it within expected tolerances? I’m considering shimming the rear mount up to bring them into alignment; is this an acceptable practice?

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Shimming is an acceptable practice. The shim stock is going to be the decision you need to make brass or steel? Then make sure you torque the screws down evenly.

Then on the other hand Lapping the rings would be a better solution in my opinion .008" wouldn't remove that much material and would eliminate the hassle of losing the shim if you decide to change the bases later on.

What does lapping mean ?

In the application or use of the term Lapping. It means to remove metal or polish a surface with an abrasive such as clover compound. In this instance a solid bar that simulates the tube of a scope and covered with the abrasive compound then is mounted in the scope rings then tightened down to the desired resistance and is rotated back and forth until the results you are looking for are achieved.

Most people look for results where the scope is tight in the rings without any evidence of binding. The worst case scenario is when the tube is bent.

 

[JFrank]

How much misalignment do you think a scope can tolerate without affecting internal function (elevation and windage adjustments, zoom etc...) I don't require or expect super perfect alignment, and i'm sure scopes are designed to tolerate a certain amount, i just dont have a feel for how much they can comfortably tolerate.

Zero’

 

[JFrank]

I’m installing some Talley lightweight scope mounts onto my new Winchester model 70 featherweight and I’m concerned with the amount of misalignment I’m seeing. When I place alignment bars in the rings and torque everything to spec, I’m seeing a vertical offset of about .008”. They have good alignment in all other directions. I don’t know if this height difference is due to the rings or if the receiver has a height difference between the front and rear mount locations. Do you think this amount of offset would put excessive stress on a scope or is it within expected tolerances? I’m considering shimming the rear mount up to bring them into alignment; is this an acceptable practice?

View attachment 1132902

Lapping will not fix that.

 

[Coyote conquest]

That would be unexceptionable to me.

 

[irishlad]

Because of this thread I bought a lapping kit and read up on how to bed rings. Used the kit yesterday.

 

[Mauser fan]

How did it work out for you? I have a lapping bar and compound and it works well when I need to use it.

 

[irishlad]

Worked well. It did take a little off the rings(low end Warne).

 

[gbflyer]

I’ve always lapped the bottom rings with the tops off. I use 220 lapping compound and stop when I have about 75% or a little more contact, clean everything up, make sure the scope doesn’t bind in the bottoms, loosely fasten the tops, level with a plumb line, and secure the hardware. Seems to work OK.

 

[Heir Kommt Die Sonne]

Is it just me or is that the same exact rifle on the box of the vortex scope?