how hot is to hot?
when does it start to affect your accuraccy??
will the heat affect anything else on the rifle??

The reason i ask is yesterday i was at the range and shooting my .300 WM i was shooting 10 round groups then walking to the target (100 yards) and back on the third set i noticed the heat waves in the scope(could not see the target clearly very wavy) and when i felt the barrel it was EXTREMELY hot. so that brings up my question.