Sounds like you're getting her a bit warm.
As for sighting in how far do you normally hunt?
I personally prefer a 100m zero and use my bdc retical to compensate. But as you have been told by your mates 200m is also good.
Also 20 rounds is alot of ammo to sight in. Just fire 3 shots to see if shes even putting them in the same area then measure to the center and move the scope to suit. Next shots should be zeroed. Gear and shooting skill related*
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