My 284 extracts and ejects fine. Any damage or corrosion in the chamber? When a case doesn't extract, what kind of effort is needed to get it out. You need to determine if the case is sticking in the chamber or the extraction mechanism is at fault.
These are pretty nice guns. They are hunting rifles (like the Remington autos), and most of them have been treated as such. A few rounds fired every year, little or no maintenance, so of course when they fail to work properly 30 years after they have been made they get a bad rap. They handle great and are reasonably well made, although whoever made the decision to leave out a bolt hold open device ought to have their pension revoked.
The only real bad downside is accuracy. Mine is pretty bad, lots of vertical stringing. I'm playing around with the bedding but nothing has helped yet, so mine maybe in the classifieds soon. Some have reported better results, some worse.