Originally Posted by DZelenka
I can't speak for Mikecr. But as acloco pointed out, 4-5-6 might be a node and 8-9-10 might be a node. But, it's really hard to say for sure when you're dealing with small samples.
And, it's not clear what role if any the wind or general accuracy played.
I like to stick orange dots on my target to give me several aim points and shoot 2 or perhaps 3 shots at each dot for each powder level and then compare the tightness of each group as well as the relative POI.