Tell the boarders to get out of the landing and just wait a little bit for the spin. You're popping off too early and catching the rail...wait til you get to the end.
like 4 ft before the end of the rail sorta dig your front skis following edge (not the leading) into the rail by sorta scissoring your skis on the rail.. hard to explain but it just happens and it will start your spin on the rail then just wait for it and you dont evne need to pop off.. it just happens.. you were popping off pretty hard there. jsut let it happen on its own
dont try soo hard, just let it flow off the rail, start turning about 2 or 3 feet before the end of the rail and once you get off, keep moving your head in the uphill direction...you'll be landing blind but you'll get the whole 27 instead of just a 180, its all about your head