Even when stalled the prop will produce thrust. It just won't be as much as when it is moving well. Also the stalling of the prop may prevent the engine from coming up to the full rpm at a standstill so you may hear the engine pick up rpms partway through the takeoff roll.

What you are finding here is exactly why the full scale aircraft changed over to variable pitch props as soon as it was practical to do so.

Using such a large prop on a scale model will probably also bring with it the torque and P effects of the full sized aircraft. In other words you will have to test for and watch out for the dreaded low airspeed power on torque roll during touch and go's and quick lift offs.