I use standard 210 match primers with 85grs of H4831sc with no problems. Was told many years ago that magnum primers aren't needed till the temp goes below 20 degrees
Well gemby that's a new one on me as well; maybe it's true but, shooting below 20 degrees F is a pretty routine matter for me since I shoot more in winter than summer, and about every year I will see below those temps in the east or west during hunting seasons..... my biggest Canadian whitetail was killed at -25 F after I had been out in that stuff all day.
I like to set rifles up to work under any conceivable condition but I am sorta anal anyway.
