Missed a few details which were include in a previous post, here they are for completeness.
New 6.5 x 55 Lapua brass
120gn Sierra Pro Hunter
Federal 210 Match primers
All seated to 2.541 "
I didn't keep the results for 34.5 to 35.5gn, the grouping for those were 0.64" 0.565" and 0.66"
The 34gn group was by far the best at 0.277"
All those groups look fine and there is probably no statistically significant difference between any of them.
Given that then if this were a deer load I'd go with the one that gave best velocity, no matter the precise measurement of the group, and shoot a few more groups using it. That will then give you some idea how it will actually perform as one group only really gives an indication that a load might be OK.
If you get a few hundred rounds out using it and are still not happy then you can change to one of the other loads and in the mean time you'll have killed plenty of deer.
Crimp the loaded round in a Lee Factory Crimp Die.~Muir