Hi, i've been loading for a .280 for about 15 years. The load I've settled on for 140 gr. bullets(I use Nosler Partitions) is 56 gr. of H4350, and a CCI 250 primer.This load is a few grains over what's recommended in the mauals,so approach with caution. I use this load in a Rem 700 Mountain Rifle and see no indications of excess pressure.