Very strange and I don't doubt it but my rifle doesn't seem to notice the 60 degree temp drop. I just checked and it was in the dead of summer when I worked on load development, reconfirmed my zero a week before my cow hunt and it was still dead nuts for POI but I did notice my group size was bigger (1 1/2" for 5 shots!!!!). I was pissed so I took it out on that cow laying next to my rifle in the previous pic. It was 35 degrees that morning when I dumped her but I only needed one shot, thank god By the way, the 286 gr. partition worked great even though it was of the blemished type
I was in reverse. Worked up a load when cold and it didn't group well until the load was on the warm side. Grouped very well, easiy extraction and no visible signs of pressure problems. Then came hot summer temps and the same load was too hot, sticky extraction and signs of excessive pressure.
�I've never met a genius. A genius to me is someone who does well at something he hates. Anybody can do well at something he loves -- it's just a question of finding the subject.�
By the way, the 286 gr. partition worked great even though it was of the blemished type 
