can be various reasons, the holes not straight etc - I've had that with a older rifle, only discovered it when I put a Night Force on it and found out the windage was all the way right - all scopes have some variation in them as well
They are $749 RRP from ATN, thats USD - so exchange rate, shipping, customs per shipment and GST all come to around $1250, so they are within $100 of the US price even after allowing for retailers margin, advertising, etc and we have a lack of volume (compared to the US) which means its can't be spread as far per unit.
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