Although temperature sensitivity is real, of course, it's not something that is going to KB a modern action, especially a typical varmint barrel. I've been loading with powders that are considered as very temperature sensitive for better than 30 yrs., and I'm not one to run my loads on the light side either, not by any stretch. For many years I've worked max charges up at cold temps, and at hot temps, then used them in reverse conditions, never had anything more than some obvious higher than usual pressures present, but nothing that screams danger!
In short, anyone that KB's a modern action is doing something critically wrong, and it isn't temperature causing it. They're either using the wrong powder, using a fast burning powder with the wrong data, or a heavier bullet than what the data was supposed to be for. Bottom line, it's not a temperature issue.
It boils down making sure all aspects of the components and data correlate. this is why I log my loads before I load them. That way when i finish a batch I can go back and verify that everything is what it's supposed to be. And that if I experience any high pressure signs, I can identify the cause with absolute certainty.
GS2
