Your post fires me up. I wanted to reload for my 280 AI for ages but I haven't been to the range in so long I don't really have any empty brass. Except for a box of new Nosler brass that has been squirreled away. Maybe I oughta crack that thing open and load some up.
I've got three .280AI's going. I use three brass head stamps, one for each rifle. Norma, Nosler, Hornady. Easier to keep separate that way. I've tried a lot of bullet powder combinations and have pretty much settled on 140 grain Nosler Accubonds with H4350 on two rifles and H4831 on one. Two rifles are absolute tack drivers, one is still sub moa but not a one holer.
One of my very favorite cartridges. I'm running the Berger 175 EH in front of RL-23 with Peterson brass in mine with a 26" barrel. Very accurate and a hammer on game.
I've recently loaded some Barns 145 grain LRX using Nosler brass and 51.2 gr of RL-17 for a TC Encore Pro Hunter. It's shooting a 1/2" group at 100 yards. I started with Ramshot Hunter but couldn't get an acceptable grouping. The goal is to find a bullet that works well on TN whitetail deer and elk out west.
The best groups so far have come from 150 BT and 4831sc. I'm out of the 150 BT and can't find any so I tried to mimic with 150 eldx and they shot very well this morning, not same hole as BT's but right at .5moa. I will be joining a 1000yd range hopefully soon and wanted a load that I have confidence in, im going to load up 25 more and take em to the range Monday to see if the groups stay consistent.