You have a very good powder for the 358Norma. At this time that powder is not available in Aust. In Australia the published data we have list 358Norma max velocities for a 250 grain bullet from 2550 to 2800fps. Bob can chime in with his exact data but the 35 Whelen using CFE223 is up in this neighbour hood. So not too far behind the Swede, but not there with it. So the Swede may not have the legs on the Whelen when using CFE223. As I said if there is a new or better powder for the Swede it may put the Swede in 358RUM neighbour. I don't doubt that with better powders the 358STA would be in 358RUM territory not line balling the Swede. The Swede and 358STA data taken from data in my reloading manuals and relating to the 250 grain bullet.
If I experiment with the 38Sambar I may get up in the Swede area with a 250 grain bullet, but I am not going to do this as I have a very sweet spot using a 200 and a 225 grain bullets. Yes the are between a Whelen and Swede velocities. The CFE223 powder in a Whelen seems to match these.
I like your rifle.