Generally, I find that 50% shot does not travel 50% of club distance, so a % might not help. You might want to experiment go to distances marks, this distance on meter with this club will go roughly this far. Try other shots instead of full swing, punch, flop, you wont need to hit as many 50% swings, you can hit 90 to 100% other shots which can be more accurate with spin, trajectory and carry distance.