What is different in these shells? One is a 16 gauge slug!!!!!! This is out of box of factory Remington Reduced Recoil Rifled Slugs!!!!!!! Just picked up a box at Rural King before heading to the range to shoot my Gold Hunter. The 16 gauge shell feed and was jammed into the barrel of my 12 gauge while shooting. The shotgun fed another shell but thankfully wouldn't go into battery!!!! Still shaking at what could have happened.