Back in the late 80's and early 90's IMR 4064 was my go-to powder for .308/.243. (I shot a pile of it at whitetails and groundhogs) I never noticed a difference in velocity when confronted with a drastic temperature change and I dont think 95% of shooters ever would notice.... BUT now that Hodgdon makes the excellent Varget powder that according to the data I have read is very temp stable, My thoughts are why shoot anything else? Unless Varget is nowhere to be found and IMR 4064 is avialable then I would have no problem going back to my old friend IMR 4064 👍.....Good luck....Hb
