ORIGINAL: iloveto4x4
Never tried the Hornady ammo, but did use the Federal H.E. stuff in my .270. They worked fine as long as it was cool weather. I shot some at sea level when the temps were in the high 70s low 80s and they locked up mygun. That makes me think that they are loaded to a higher pressure.
Federal H.E. may be.... I am not sure how they are loading those, but Hornady are not loaded to higher pressures. They use a proprietary powder, that results in higer energy at the same pressures. This is their own special blend / type of powder. I have used the Hornady in 95 + deg. weather in the dead heat of summer, and there were no case issues, sticking, pressure, or anything.
Try some of the Hornady light Mag ... see if you like it better than the Federal.
God Bless
MET