SD over a complete accuracy node?

[DenisA]

This is probably a silly question. Theres been lots of discussion in the past about SD of a given load, but I've been wondering if theres a practical use for SD over an entire node. So hypothetically 25 - 30 rounds over 0.5gn powder(5 - 6 groups of 5 shots in .1gn increments). I imagine the SD of a complete node might give an idea of how condition proof it might be when compared to the SD of other similarly accurate nodes.

[johnk]

.... and if you calculate it, do you use STDEV() or STDEVP() in Excel?

[DenisA]

I better add that when I say condition proof, I mean ambient temp changes from day to day. That wasn't clear at all.