Blems - can also be batches that failed the precision tests.
Not bad, just out of spec.
Specifically to the Nosler blems sold by SPS - how do you know this to be true? And does your statement apply equally to bullets, brass, and loaded ammo, or only to one or two of those?
I don't mean to "challenge" you, I just want to know how you know this, as what I have learned previously implies the blem status is limited to cosmetics.
EDIT - I have seen odd things like 251 grain .338 E-Tips in the past, and these would seem to be a data point for your contention, but at least SPS/Nosler were up front about the one grain over weight in the case of these.