How long do you cook a 30 pound turky?

A 30-pound turkey would usually take around 4½ to 5 hours in a 325°F oven to cook all the way through. To be sure the turkey has finished cooking, use a meat thermometer and take the temperatures in several areas (thigh, breast, stuffing) to look for 180 °F. Always let the turkey rest for 20 minutes tented with foil to fully absorb the juices for the very best taste.