i figure it out....with that little spring on the feed lip...it would not let the round get enough upward angle to enter the chamber. Now with that spring gone, it feeds!
edited: went to the range today. Had a whole bunch of people gather around me! The AA921 mag will not feed. It looks like it does not have enough upward angle on the feed lip to guide the round into the chamber. It would hit just below the chamber. With the springs out, it definitely is a little better allow the round to get more angle but still won't feed. I have fiddle around with it for more than 3 hrs now,if anyone in the lower mainland have a mag that works, i want to meet up with you and try yours!
Check for any plastic mold flashing on the front of the feed lips, but it sure sounds like your mag isn't seating all the way.
The nose of the round shouldn't really have anywhere to go but into the chamber, the front of the feed lips will pretty much only leave the chamber exposed.




















































