Re: Powders for 280AI w/ 140 gr bullets
Hodgdon and Nolser both have reloading data for the 280AI and I wish I could help but haven't tried 140gr in my 280AI.
Since my 280AI likes IMR-7828ssc with 160gr bullets and Nolser has data for that powder with their 140gr bullet that be the first powder I would try.
I have a 27" long barrel on my 280AI and mid loads I'm at max velocity give you good example. Hodgdon has max load of 61.5gr/IMR-7828 with 160gr AB @ 3043fps and in my rifle 59.5gr/IMR-7828ssc with 160gr AB @ 3038fps.
I've got a # 1 rebarrel to the 30-338mag.