Wow, yea, must be that mag. Also check the feed ramp. Another suggestion would be to chamber it, and unchamber it and examin the bullet to check for nicks and scratches beyond the normal ejector/loading marks. I had read of such problems on another forum and these were the suggestions that were given. Just passing them along.
If you remember or can find a picture of a working Mag, you can possibly bent it back in shape. If you do so, the metal will be weakened and over time will possibly fail again. A good "quick" fix until you get a new one though. I'm sure someone here will chime in with better ideas though.... LOL