Just went out with my first group of loads with my latest buy, a Cooper Model 52 280 AI. Been waiting on the new Leica scope to put on it. Tried some Retumbo, some H4831sc and some IMR-4350. Bought some Berger 168 VLD's and Nosler Accubond 160 grain to start with. So far the H4831sc with the Bergers look good, several of the 168's looked better than the 160 Accubonds. It's early on so time will tell. If you have any good 280 AI load feel free to pass them along.