Yes over tightening the rings can affect the scopes ability to track correctly, hold point of impact, and can even crush the tube. Depending the brand of rings, 15-20 INCH pounds is all that is needed, and it should be listed on the package or inside. I have a Wheeler Fat wrench, but I find it rather crude, the indicator bar that travels up and down the scale fills the gap about 20-25% between 10-20 inch pound lines so you never really know if you are at 15 or 17 or...? Get a good quality name brand torque screw driver and be done with it.