Jimimac
I have not shot that exact one, but i do shoot the .458 Nosler for elk hunitng and I have shoot Hornady 300 grain and 350 grain .458 a bunch in that sabot. They all shot very well.
One of the keys will be can you get that combination down your barrel? Another thing a lot of people are doing is using the Harvester 'crush rib' with the .458 so that they can get them down. I think it started over on the Savage board and they have had really good success with them.
For the Nosler's I am shooting 110 grains of T7-2f, touched of with either a Renington 209-4 primer or a 25 ACP depending on which gun i am shooting.
I did have shot a couple of elk with this load, this year I shot a cow @ 176 yards - pass through... It was excellent.