The Tormach chucks are no better than "ok". You have to REALLY crank the snot out of them to make them secure on larger drills, and that is hard to do without the key slipping. I nearly always use ER chucks for drills - they never slip. Doing a 0.404 hole in one pass is also going to be tough. You'd be much better off drilling a 1/4" pilot hole first. Also, a hole that large, and that deep, will pretty much require lubrication, not just coolant. Very likely you're welding chips to the drill.
Regards,
Ray L.