I tried to avoid the 140 comment, but you did if for me!
Temperature-sensitive powders can definitely change POI when it gets much colder or hotter than when the rifle was sighted-in. In fact this phenomenon was how I got into testing powders at different temperatures in the first place. I tell the story in Gun Gack II, where a very accurate .270 Winchester that shot 130's and 150's into the same small group at 70 Fahrenheit did NOT down around zero. The 130-grain groups opened way up, and the 150's shot about 3 inches from point of aim.
“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.” John Steinbeck
