@markg208 maybe it's me but I see your load development differently. First, though, what are you using to measure your charge weight? Have you cleaned the carbon out since you started load development? What scope are you using? What's your setup for how you are shooting groups (prone w/ bipod/rear bag, bench w/ bipod/ rear bag etc)? Where do you live and what are the temps? Are you in the south w/ high temps, humidity, mirage even in the winter?
Here is where I would search from your previous pics.
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First, that group is under an inch. It's actually 2/3 MOA.
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Second, shoot a couple more 3 shot groups at 43.7, 43.9, 44.1 and see what things look like. The ES between 43.5 and 44.3 is 48fps…that's 6 shots over 0.8gr of powder. That's not too bad.
Even though you only shot 3 rounds at 43.9 it had an ES of 16 and it's a nice round group. 43.5 had more vertical and 44.3 was almost pure horizontal. A rifle that shoots 2/3 MOA w/ an ES of <20fps will do really well out to as far as that cartridge (.308 Win) and that bullet are capable.
That said, if you can get some Varget, N540, or IMR Enduron 4166 they would be worth trying for sure.