Well I appreciate everyone's help and input. From a previous post I have some late fall hunts this year were we will be experiencing some very cold temps. Thought I would try the H4350 "extreme powder" from Hodgdon. They are full of it. Very frustrating. We put some rounds in double freezer bags for 6 hours set at 32. Everything was set up and the rounds were fired through the chrono within one minute of leaving the freezer. Had an average of 226 fps loss. How they claim what they do, well I hope this also helps anyone with these concerns over H4350.