I'm thinking the material used to fill the space that was taken up by the old Remington extractor is to thick and not allowing the Sako extractor to hold onto the case rim long enough. Below are two pics of my Sako extractor. Notice my Smith didn't use fill material and the extractor has worked flawlessly for over 700 rounds. You can see how much more grip the extractor has.
that makes sense. he chucked it back up in the lathe when i took it to him to see why it wasnt ejecting cases properly and opened it up a little more.
what caliber is yours? mine is a .308 bolt face