From: lora
when I make donuts from refrigerator biscuits I
use the top of a 2 liter soda bottle for cutting
the donut holes, it is perfect size and the fried
donut holes are perfect size.

Here’s the recipe in Dining On A Dime.

Refrigerator Donuts

1 can refrigerator biscuits    powdered sugar or
oil for frying       cinnamon and sugar

Punch a hole in the center of each biscuit. Fry in hot oil until donut puffs and is golden brown. Turn and fry the other side.  Drain on a paper towel. In a paper sack, put about 1 cup of powdered sugar or 1 cup granulated sugar and 1 teaspoon cinnamon.  Drop donuts into bag and toss until coated. Serve warm. Makes 10 donuts.
*A 1-inch-diameter piece of clean metal pipe cut down to 3 inches is a good donut hole punch.
* The powdered sugar or cinnamon and sugar may be saved to use again.