I have been focused on developing loads which work in all temp ranges, has anyone noticed if using a mag primer in a non magnum caliber can help with temp sensitivity?? I got to thinking maybe that hotter flame front would be less effected by temps

In general, I use ball powders whenever possible. In the larger cases (all my hunting rifles use large cases) all my hunting ammo uses magnum primers. Even back when I hunted with a .308 Winchester exclusively, I used magnum primers. Where I live, hunting temperatures can go from 45 degrees to -10 in a single 24 hour period.

My handloads are developed using magnum primers, so there are never any surprises. If I happen to find a certain combination that doesn't work well with magnum primers, it isn't used for hunting.

Though I have had primers misfire or FTF, it has never happened while hunting. That doesn't mean it never will, and in my opinion, proper lubrication of the firing mechanism is more important than primer choice. Firing pins just don't move as fast or hit as hard at -20 as they do at 60 degrees.