that is a neat rifle and I think it is a clone of the Marlin M60. I like the forend lines and the built in sling is kinda neat too.Sorry for the poor quality cell phone picture:
The extractor does get worn over time, and it sounds like yours is just not catching the rim as well as it did way back when it was new. Works fine when fired becasue it really doesn't NEED an extractor to work (have been some guns, like the Beretta Minix and Jetfire pistols, theat had no extractor at all).
Been some debate, but believe it was a hi Standard made rifle, sold under the JC Higgins (Sears) trademark. Will go looking for a parts diagram.