To be fair, I haven't really had to grind behind a spotting scope yet, but I can imagine, like a day behind any monocular scope, using essentially just the one eye...
The folks over at AMPRO sent me down a couple of the higher end Bushnell long-range scopes to check out. Sadly, life has a way of getting in the way sometimes, so I only really had enough time to play with one of them - the Bushnell Forge - 4.5-27x50.
Clickbait title aside - there are a couple of reoccurring problems I see when people discuss zeroing a rifle. Are you doing any of them?