Going straight to the point here................can heat effect POI shift on a scope? Scope is a Nikko Diamond MK3 and the gun is a HW97k so usual pcp cylinder overheating is excluded. Only asking as I have recently experienced a POI shift 2 times (shooting low about 1"-1.5" between 25m-30m) and both times in scorching heat. Been shooting for about 4 hours under direct sunlight (and yes got sunburnt too ) last Saturday and today and after about 4 hours shooting I started hitting low. Chronod the gun and fps was constant 770's so no velocity problem there. Things indicate scope POI shift because of the heat but I have never heard or read of anyone experiencing such a problem. Is this possible or could the culprit be something else?