Hey guys,
Haven't seen it mentioned yet, so I'll risk boring you with a little history here. The 22-250 was actually where H-380 got it's name. It was one of the original USGI surplus powders that Bruce Hodgdon started the company with. He found that 38.0 grains under a 52-53 grain bullet was THE load for his (then wildcat) 22-250 varminter. When he bottled the stuff and started selling it, it suddenly became H-380 in reference to that load.
(and yes, use the current data for this combination, despite the history here!)
Kevin Thomas
Lapua USA