Re: FINALLY Got to Shoot My 338 Ultra Mag.
I know this is apples and oranges, but after all the hype of R17 and 208 AMAXs, I tried it in my '06. My gun hated it. Most of my load development is 200yds or further depending on weather conditions. Going up near max load had the 208s moving at 2730ish out of my factory 22.5" sporter. Again, the gun hated it to the tune of 4" vertical dispersion at 200yds as the best group confirmed over and over.
I changed powders to h4831 and I'm not getting the velocity with the 208s, but the accuracy is back down under MOA. For me, vertical needed less powder, not more...
I think you're still too hot and judging from your chrono numbers, I'd look around 88.5. If you don't want to drop that far, looking at your pictures, 94.5 might be a node as there isn't much vertical, just a bunch of horizontal.
But before all that with no offense intended, focus on "you". Make sure you're doing everything right. Proper weld, not torquing, pulling straight back with hand, pulling trigger straight back, etc. Dry fire or shoot a 22 a bunch while practicing all that.