Originally Posted by Sundance
I'm familiar with range finding on detail such a the frayed string or some low contrast detail around the target..and it is part of the routine..
My guess at 5 M over ranging is a bit vague as I only have marks going to 50M....need to spend more time trying to figure it out but it's always worth asking on here to get some pointers..
You ideally don't want low contrast, you want high contrast, high detail. Yellow & green against black is the highest, white/black is lower because it can glare more.
What makes scopes shift isn't known or publicly known. There's been a scope manufacturer that's stuck their neck out of the bunker a 2nd time, but as as the scopes aren't on sale yet, no one knows. But there are scopes that shift more than others, suggesting it's a material variation or design difference.
My suggestion on looking into for a manufacturer it would be to buy the best and worst, and cut them open to find out where the differences are