I started out using IMR 4831 (55gr/139 Hornady sp) in my first .280, down in East, TX. It shot great at warm temps ( when i worked up to it) and even around freezing later that winter. I used tons of IMR 4350 in my first 7mm Rem Mag and same thing. I used CCI 250 back then. Later in life, in OK, I worked up some loads in an old 1917 Enfield 30-06 with IMR 4350. I used all Sierra bullets ( accurate and cheap, I was in Bible School so was just playing at the range) I shot out to 275 yds ( extent of the range) in hot summer and later that winter around freezing and a bit colder, zero never changed. I had no chrono, but couldn't tell any diff. I used Remington cases ( once fired range pick ups, but I was learning about prepping brass , this was 1988.) all Pro Hunters (flat base) , 59/150; 58/165; 57/180 and 55/200 gr. I had some vertical stringing, so went to CCI BR2 and it fixed it, so have been using them ever since! I started using H4831 ( later SC) in early 90's,here in Utah, along with H4350, in several calibers. My point is that the Hodgdon Extreme Powders are wonderful, but in most cartridges, if care is used in load workup, you will have no issues with IMR. Having said that, H4831 (and SC) is so good its boring, ha.
IMR 7828 is another good one because (it used to be) the factory powder in the 7mm Rem Mag. That ammo in that caliber was/is used all over the world! Hot, cold, its got to be a good one! I once used 76gr/ Winchester brass/ R22/180 Barnes/300 Win Mag in Namibia. It would get down to 20 deg or so at night, and by noon ( mind you) it was 120 deg! We had no issues, that is an honest 100 deg swing! So, alot depends on the round, but if I ever have a doubt, I go with H4831sc or H4350. I still keep some IMR powders though. I just like how it "smells" when I open the can! ha Have a ball pard!
