Preheat the oven to 325 degrees F (165 degrees C). Place a rack in the lowest position of the oven.

Remove turkey neck and giblets; pat dry with paper towels. Place breast-side up, on a rack in a large roasting pan.

Loosely fill cavity with stuffing. Rub skin with butter; season with salt and pepper.

Pour 2 cups of turkey stock into the roasting pan.

Loosely tent turkey with aluminum foil; roast for 2 1/2 hours, basting with pan juices every 30 minutes. When drippings evaporate, add remaining stock to the pan, 1 to 2 cups at a time.

Remove foil and continue roasting until a meat thermometer inserted in thickest part of thigh reads 165 degrees F (75 degrees C), about 1 1/2 hours more.

Let stand for 20 to 30 minutes before carving.