after youve checked that your using the right powder, hulls and wad, and aomount of shot, compress the wad with the spring loaded feature in the front nozzel where the powder and shot comes out.. use more and more compression until it forms ok.. this pressure can be adjusted with a screw on a sleeve that holds the drop tube.. crushing can also be caused by something angeling the shell, .. the crimp starter can be adjusted in height somewhat and it may need to be lower. my mec jr book says to bulging case over brass:: use case with more capacity,, use shorter wad,,,use less shot,,,use a denser powder,,,use more wadd pressure, 40 pounds is usually suffecent... these are in the book under trouble shooting bulges.. do not change loads without folowing another rescipie.. you cannot change hulls in anyway from loads they can have differning interal sizes that cant be seen from the outside.. so use the correct hull the book calls for.. my load now needs a 52 pound compression on the wad to fit properly... good luck dave..