I personally believe anything over 3200 with 140's is over pressure, and those that claim 3300 and above are living on borrowed time,the 280AI is a great cartridge but some expect it to be more than it safely can be!
Here, here... I've been using a load that dogzapper suggested in my Ackley lately which is 60 grs of IMR-4831 with 140 gr Nosler BT's. Very, very accurte with no "traditional" warning signs.
