My 2c worth: 3-shot groups are indicative, and over the eight groups shot + your more recent groups, shows the rifle&shooter general capability - at the top end of what I've read on the Ruger, so it looks like you have a good 'un and are shooting it well - but I wouldn't want to pick between any of these loads based on single 3-shot groups of each charge weight. I'd now be loading up 20 rounds each of 40.0, 40.5, 41.0 and 41.5 and shoot 4x 5-shot groups at 200 or if available 300 metres, then decide. Assuming you are preferring as high a MV as possible, if you started with 41.5 and 41.0, then later the first groups with 40.0 and 40.5 did show significantly more dispersion - and you were confident this was correct - you could pull the rest of these lower charged loads to keep total shot count down if that was important. Then time to refine the seating depth....
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