It's sounds like a Model 60 (the later version of the Model 99).
If it has a grooved receiver, manual bolt hold open (push in to lock), brass inner mag tube and a micro groove barrel it's a Model 60 action/rifle.
But....The first walnut stocked versions of the Model 60 were called & marked 'Model 99' though,,if that isn't confusing enough!
There was also a 'Model 99DL' (DeLuxe) but I don't recall what made it different from the standard. Too long since I worked there. Perhaps checkering or M/C stock,,don't really remember.
The poor quality sintered metal feed throat/ejector used in the earlier production rifles caused most all of the problems with these. A change in about 1973 solved most of the problems.
