I have an older M1 Super 90 that will "ramp" an extra round when the magazine and chamber are full. I've heard that Benelli has eliminated this feature on guns currently being manufactured. A friend has a year old Super 90 that doesn't seem to want to "ramp" an extra shell (s/n M425423). Does anyone know what the last serial number was for Super 90s that WILL "ramp" an extra round?