Well, as I posted earlier about the .223 and the 75gr BTHP beating up on me I ran some loaded rounds over the gauge. I would think that since I have runout from .005 - .013 with most being .009 and up that would be a contributing factor. I used the flat steel to square some stuff up trick and I had runout from .002 to .004 after that.
I checked the ammo for my rifles that always seen to shoot great, runout was under .005 the 2 rifles that I have been fighting for 2 weeks now had runout on probably 95% of the loaded ammo over .008 and up to .014"
So yeah, you could say interesting.
My curiousity is if run out is the reason for "2 in/1out" groups. Lets say zero run out equals bughole groups. I measured 18 rounds of ammo I loaded half assed and about 50% were ~.005. A handful were under .002 and slightly more were over.007. If I were to randomly shoot 3 shot groups I'd have a 3% chance of getting the best 3 in one string, and a 60% chance of a combination of the others (which would end up as 2 together, 1 out) and a 25% chance at hitting the median, essentially a larger but equal "group"
.........aaaand I've gone cross-eyed. This is mathman's territory.
