i've seen a good batch vary as well. H was eating humble pie when we found our good batch would not group and that the fall and rise could perhaps not been wind after all... i picked out another tin from the batch and they were better.
weighed groups dont seem any tighter than unweighed groups, and even picking different weights doesn't see a shift in POI in my experience, however, better grouping pellets have a better weight consistency.
sizing seems to tighten groups, but not to the same degree as a good shooting batch, which shoot well unfettered from the tin. H thinks so as well. But you need to find the size for the barrel, and i suppose some barrels may not like it, but 4.48 or perhaps smaller seems to suit the wallies.
i think it's down to just finding the batch and going with that... and buying as much as you can, when you can... stated head size, make and label are irrelevance to the target anyway...
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