I've seen various posts where long range shooters record temperature and humidity conditions when making what I consider extraordinary shots. I am currently working up some loads for a couple of my rifles, namely a 270WSM and a 7-08. These days, when I go to the range to test my loads, it is usually upwards of 20C (68F). Will the external ballistics change when I go hunting in the fall or winter and the temperature changes drops to 10C (50F) or even down to -10C (14F)? Are the ballistic changes that I hear of affecting bullet path or affecting the way powder behaves. I've even considered putting my loads in a thermos lunch bucket with some isolated ice pack to cool them down and simulate a temperature closer to hunting season. Am I way out in left field here?