My range is just outside my back door. I anticipate subzero temperatures to test hunting loads, developed in warm temperatures. Need to make sure POI isn't affected by cold weather. I try to imitate conditions, I may run across during our hunting season. We can have lows in the 40-50's on the warm side or 20-30's on the cold side. I don't like surprises. I'll put the rifle outside while I hang four targets. After acclimatization, go back indoors and fire another shot, 20-30 minutes later. Repeat till all four targets are used. Mark those targets with same color highlighter and record pertinant information...............day, temperature, wind speed and direction. Next time, using a different color highlighter. Do that several different days when conditions are conducive. Compare the results/groups.