If the rifle is a "controlled rounf feed", it means the BSE has to be loaded into the mag and as the bolt clides forward, the BSE will slide across the bolt face and engage the extractor.
[You maybe be able to chamber the BSE and lightly touch the base of the BSE , then press in on the middle on the extractor, which will lightly "spring up" the front of extractor. to allow the extractor lip to over-ride the case rim , then push forward on entire bolt unit and the BSE will engae the case mouth, allowing extraction as you pull the bolt rearward.
A "push feed" bolt the extractor move to the outside, over-riding" the case rim.
Hope this helps.