Use a Ball Nose Spring Plunger

To use a ball nose spring plunger, first place the plunger handle in the water and squeeze the top of the plunger. The ball and spring plungers will rise quickly, so hold on to the handle and release as soon as you feel the plunger enter the water. When you get close to your target, plunge the plunger down into the water and wait for it to come up.