Blocking Heimerdingers ultimate turret [GAMEPLAY]

As Yasuo, when fighting Heimerdinger I used my windwall to block his supercharged turret's shots. The shots from the turrets seemed to pass straight through the wall, but when they hit me I took no damage. This occured every time I used wind wall against his supercharged turret. I do not know if the same happens with normal turrets. It's not gamebreaking, but still a somewhat tacky bug.