First make SURE the magazine is removed, and that there is no live round in the chamber. You can verify that there is no bulleted round in the chamber by measuring with a cleaning rod. Compare it to an empty cartridge placed next to the chamber.
Clearing a failure to extract on semi-auto rifles is fairly simple. Take a block of soft wood (a 2"x2" or 2"x4" is good) and rap it smartly against the charging handle. Do this a couple of times until the charging handle retracts the bolt enough to extract the empty cartridge.
If the rim of the cartridge is damaged, lock the bolt open, and use a cleaning rod from the muzzle to tap the case out. If the case is still stuck, try dribbling some light oil (WD40, solvent, etc) into the chamber and let it soak in. Extraction failures are usually caused by dirty or rough chambers, or soft brass, or both. In your case, the surplus CAVIM ammunition may be the culprit. Many users have reported problems using this surplus ammo.
HTH
John