Summer vs Winter velocities and temp stability

[Koda]

Maybe, but in this case I am going to take the advice of a very seasoned shooter/reloader and start with 4350.

Between the two powders I agree, thats what I would choose.

 

[orygun]

Between the two powders I agree, thats what I would choose.

I also have 3031, which is what the Roberts started with, but I agree that 4350 is a better suited powder for that cartridge.
I have to give Ken Waters credit for that, but through the eyes of @Spitpatch .

 

[osprey]

Many programs like Strelok pro, you can enter your measured velocities at a higher and lower temp and it will calculate temp stability factor in %. You can then use current conditions to predict the fps change and help with aiming solution.
A 40 fps change in velocity with a high bc 7mm bullet would only result in a vertical shift of about 1.5" at 500 yds according to Strelok pro. A 10" poi shift summer to winter sounds like a bedding problem.