Working on a load with 215 Bergers and a goal 2850 fps. Starting point was 74 grains of H 1000 and 1 3/8 groups at 2566 fps.
next up was 75.5 grains 3/4 inch groups at 2678 fps. At this point 76 grains gave me 2680 fps, 76.5 = 2695 and 77 = 2707 fps but the groups were patterns. 2 1/2 to 3 inch.
I've never had groups open up this much between accuracy nodes before. No hard bolt lift , some flatting of primers but doesn't have me concerned yet. 
Yesterday was 100 degrees out but was shooting undercover . This morning I'll go thru the rifle looking for things that might have loosened up. Wished id had some more of the 75.5 loads that shot those 3/4 groups to see if in fact other things might be the problem.



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In my 300 win mags. I got up to 2700fps out of 220gr Hornadys. accuracy is at 2650fps. 2850fps is probably wishful thinking unless you have a 28" Barrel.

2885 FPS in a 24” obermeyer. 78 grains of H1000 Norma brass. 210 LRAB. I would expect to loose 75 ft bumping up 5 grains.
It’s hot but shoots like this.