I see there is a post about this 7 months ago and no one ever replied to him.
Just in case he didn't get an answer, I had the same rough trigger blade problem with my new WSM B-Mag. I carefully removed the blade and no springs went flying. I polished the blade and filed the slot in the trigger, it had a burr in it. I also added an .008" shim on the left side of the blade to keep it true. It is now very smooth.
Pic attached:
https://imgur.com/a/0Wzza
