I own 3, 597's. One I have had for 5 years, one for a year and the other is brand new. Can you tell I like 597's.
When I bought my first 597 I had a couple issues with it. Mostly failures to fully eject the ammo. I started reading on line and decided to see if I could improve the situation. I was nervous at first as I am far from a gunsmith but they are pretty easy to work on.
There are a couple things that I think you should do. First take the trigger group out an give the internals a good cleaning. There are good instructions on how to do this in your manual, look on line for a copy if you dont have a paper one. Also look here:
http://www.rimfirecentral.com/forums...play.php?f=218
scroll down to the sticky with the best 597 threads and read, there are many good tips. Spray out the trigger group with brake clean or Rem cleaner etc. use a touch of dry lube in the spots shown in your manual. Remove the guide rails and bolt, clean the rods and bolt. polish the rods and lightly lube. Polish the contact surfaces of the bolt. Reassemble being careful not to over tighten the guide rods, they will bind and mess up your bolt travel.
This will probably take you less then an hour.
Once you get your gun back together head out shooting with a few types of ammo, rimfire semis are known to be very picky about ammo. I find most high velocity ammo works pretty good with CCI mini-mags working the best, for me. I have had the least success with Rem and Winchester ammo.
If you are in the Calgary area Id be more then happy to walk you through break down and cleaning this gun, send me a PM.
If all else fails send it Remington, but I have a feeling that with a little time, some Rem cleaner and a few types of ammo you will love this gun.
Hopefully the extractor isnt missing.