I don't know where the author of the piece that says a 1300 will auto eject a round on it's own but that's pure BS. I've got a youth model 20 gauge 1200 and my brother has a 12 gauge defender and neither will "auto eject" and both are in good shape, with nice smooth actions.
The only way to get a 1200/1300 to properly eject a shell is give the forearm a good hard pull to the rear. the action of the forearm/bolt assembly moving easly to the rear is just a nice smooth action and has very little with any "speed pump" BS. Any pump well broken in action will do the same, my old Wingmaster sure does!