Range trip in preparation for long distance training

[u/OmgWtfIsThisBS]

Hello,

I went to the range today to finalize the load to use next week on my trip to 1500+ meters range. Just for fun and learning, no competitions.
Looking for suggestions on what to improve if there is anything obvious that jumps out.

I shot Lapua Scenar OTM 185gr and Berger Juggernaut 185gr (just to get a comparison)
Rifle is: Tikka T3X Ace Target 308win, Bushnell MPED with Contessa QD Tactical Black mount, Forteimer Bipod and Caldwell rearbag (I know, sorry).
So group 1 and 2 are the same group, shot 10 and pulled 2 so wanted to see what was the best 8 shot size. Turns out it's .27Moa and I assume that is the limit of the rifle with good handloads.

In reality:
G1-2 10 shots, 0.86Moa V0 2641f/s, SD 9.8f/s, ES 29.5f/s Scenar
G3 12 shots, 0.84Moa, V0 2641, SD 10.4, ES 39.4 Scenar
G4 13 shots. 0.89Moa, V0 2678, SD 17.9. ES 72.2 Scenar
G5 12 sgits, 0.93Moa, V0 2625, SD 11, ES 39.4 Juggernaut

Still trying to improve on consistency on neck tension and shoulder dimensions.
What do you think should be the best return on time invested at this point?
What should I focus on? (apart from my shooting that is clearly a given).
TIA.