Ive got a theory. Ive noticed with all mags, as the top round is stripped off the lips, the rim gouges the bullet of the next round. It puts a good little mark straight up the bullet, even with the lower pressure of a well broken in rotary mag. Your top round wont have the gouge and this could be causing the flyer. Try this: load your mag up, pop it in and #### the rifle twice, chambering and then ejecting the top round, gouging the next and chambering it. Let us know how she goes!