The extractor goes into a little cutout on the outside edge of the chamber. This cutout gets cruddy easily. I believe it can get so cruddy it pushes the extractor tip aside enough to bend it slightly outward The result can be seen as looseness of the extractor in its channel in the bolt. This leads to slipping on the cartridge rim. The extractor has no spring but has some spring itself. To tighten mine I removed the bolt carrier from the rifle and put it on a soft faced vice with the extractor against the vice jaw and only the top 1/2 inch of the bolt showing. Using a plastic faced hammer I tapped the extractor tip lightly toward the centre of the bolt. The result was that the extractor was tighter in its channel. I was willing to risk breaking the tip but judged the metal mallable enough. You have to make that decision yourself.