I remember reading a study recently where a guy tried to test various powders for temperature sensitivity. Can't remember if it was in a mag (Shooting Times or Guns and Ammo?) or on the net. If I recall, he loaded rounds with various powders, kept some in his freezer and left others out in the sun. Went to the range with a cooler and shot both hot and cold over a chrono, recording the results.
Don't rememberr all of the details, but I do remember that IMR 4350 had a pretty big variation. I had just got a pretty good deal on a 8# jug, and bought it, therefore was interested.
Temperature sensitivity is grossly over sold and until they came out with a line of powders claimed to not be temperature sensitive no one even thought about it. Just another case of marketing hype. The only time it really could matter in my opinion is if you work up a load when it's real cold and then use it on a really hot day and you were already at or slightly over max to begin with in cold weather. This I've done with W760 and it was too hot in hot weather but in honestly might have been in cold weather really but just not enough to manifest in the way of a stuck bolt on firing.
Yeah I pulled them and made a note to never use that load again. Shame really as it sure was accurate the most accurate 7-08 load I've ever developed in fact.
A forum community dedicated to the great outdoors and hunting enthusiasts. Come join the discussion about hunting, fishing, survival, archery gunsmithing, optics, reviews, accessories, classifieds, and more!