I see 41.5 high then down to 41.7 then up to 42 then down to 42.2 and I'm thinking either two out of four are you or that isn't the load.
42.5 through 43.2 look like there might be a node there. You might make and shoot 3 each of those and see what you think. 43.7 through 45 are showing a lot of vertical. Again it is either you or that is not the load. If there is a node at 43 then, in my experience, there should be another node in the range you shot - like the man said above, maybe around 45 but watch yer pressure.
I guess I am old-fashioned - I think 200 yards is fine for determining charge weights. On first try, you used single shots. Now that you have a better idea, I would switch to 3-shot groups then 5 shot groups.
FWIW, I have four .308 rifles, 2 bolt guns and 2 semi's, they all shoot the same ammo pretty well. I use Lake City LR and Lapua cases , IMR 4064, Federal 210M, and Sierra 175s. My optimum charge weight is 41.5 grains. My COL is 2.825 plus or minus about .005 (mostly bullet length variation), I seat with a Winson die. I use a .332 neck button. That yields a before-seating neck ID of .303. A .333 button also works but neck tension is lighter so not quite as good when feeding from a magazine. Because Federal primers are pretty soft, anything over about 42.5 grains is too hot in me. You might try that combination. In my guns it shoots pretty much the same as FGMM.