Special equipment: a 30-quart pot and a large, sturdy propane burner
Pat the turkey dry very thoroughly. Sprinkle generously, inside and out, with salt and pepper.
Fill a 30-quart pot with the appropriate amount of oil (see Cook's Note) and heat to 300 degrees F. Carefully lower the turkey into the oil and bring the oil temperature up to 350 degrees. Fry until the turkey registers 155 degrees at the breast; start checking after 30 minutes.
Carefully remove the turkey from the oil and transfer to a large cutting board. Let rest for 30 minutes before carving; the internal temperature will increase to 160 degrees as the turkey rests.
To figure out exactly how much oil to use, place the turkey in the pot and add water just to cover; make sure the pot is at least 4 inches higher than the water line. Remove the turkey and measure the water that remains -- that is how much oil you will need. Warning: Using too much oil risks overflow and cans cause a fire.