Mini-Donut Batter Dispenser

This is used for dispensing batter into a deep fryer for making mini donuts, the type I am creating this for is to make the mini cinnamon/sugar donuts you find at fairs and events. Also known as "Those Little Donuts"
(A 5mm or more diameter spring can be added between the plunger shaft and cap at the top, to make this item a little easier to use.)

Recipe:
1 egg -- lightly beaten
1/2 cup milk (Adjust to make a semi-runny batter)
2/3 cup sugar
1 tablespoon oil
2 cups flour