Quite interesting that H380 is very accurate and maybe more so that others. It makes sense cause a slower burning powder might not be as fussy and maybe velocity is more consistant??
Pressure is also pretty low also, not pushing 223 SAMMI limits at all...
with a 55 grain bullet and 29 grains, pressure is like 41 or 42,000 PSI... so its easy on the brass, if you desire long brass life also.