jim62,
you might be getting just a little bit over zealous.
I had a couple 22-250's that both loved H380 with 55gr NBT's, I later bought a 220 swift and tried H380 with 55gr NBT's in that rifle as well.
The 220 swift has a slightly larger case capacity than a 22-250 and is absolutely more temp sensetive with H380 than it is with a 22-250.
Also if you notice all of hodgon's Extreme powders are extruded.
Most other manufacturers extruded powders are close, for the most part(not all, so dont fly off the deep) it is the ball powders that are the least temp. sensetive
