info for you
It could be a couple of different things going on with it. I would double check and make sure to clean out the bolt around the extractor first. Clean out around it and make sure that it springs out and holds a round up against the bolt face. Sometimes dirt cause it to not spring out and move back into position. I use a good spray cleaner to clean it out myself. Make sure to spray the spring pocket as well. I would also make sure the hook is still good and not broken off.
Next I would make sure that the feed lips on the magazine are not bent out. They can cause jams like you are experiencing. Make sure that the magazine is clean as well since dirt and oil can cause it to mess up on you as well. Load it completely after cleaning it and use your thumb to slowly push the rounds from behind just like the bolt will be doing. Check to see exactly what is going on when you slide it foward. If it is allowing the round to jump up too quickly, you can get the stovepipe like you are describing. A new magazine might be the best bet if you have a problem and don't feel comfortable with shaping the feed lips like they should be. Best of luck with it.
