I own and shoot a Rossi 357 mag carbine. I use it in NRA Cowboy Rifle Pistol Cartridge compitition. My load is Rem brass, CCI small pistol standard primers, 7 gr Unique and a 125gr Rem sjhp. I use a Lyman Reciever Sight. At 100 meters, I get under 2 inches from a rest and just over 2 inches shooting offhand.
My oponion of the rifle is that it is cheaper than a Marlin and much stronger. It isn't made to mount a scope on. I had to drill and tap it for the Lyman sight but my gunsmith did it for only $20. It really is not a gun you would want to shoot with a scope. Effective range for hunting is only about 100 yards and the receiver sight does just fine out to about 150 yards.
For hunting in Western Oregon it would be great and at the ranges that you see game over there a scope would be a hindrance anyway. At close ranges it should be good for anything from black bear to deer and even an elk at close range. "Elk", yes, they shoot them wit 50 cal round balls don't they? I would feel more confident with a 180gr 357 from a 20 inch barrel on an elk than a 50 cal round ball any day.
If you are hunting Western Oregon, take a bigger gun, with a scope.
Just my 2cents.
Sixgun