AkMike,
I've myself got a #1 in 450 NE, but I put a new 28" 3-groove Pac-Nor in it. Went 3 groove because I shoot blackpowder in mine for the BGR Blackpowder Express events. My theory was that there are less corners in a 3 groove barrel for fouling to build up on, seems to work so far.
Remember to take a bit off the top of the safety catch and give it a very slight bend downwards so that the empty cases clear the action easily, and don't get caught up on the safety.

Regards,
David.