Cook rice according to directions in 3½ cups water. Heat 4 tablespoons butter in a large skillet and sauté onion, celery, and garlic.
Once rice is done cooking, add to the onion mixture. Stir in raisins, sherry, bay leaf, salt, pepper, sage, marjoram, and thyme and mix thoroughly.
Loosely stuff mixture inside turkey. Place any remaining stuffing in a greased baking dish, then cover and refrigerate until ready to bake. Tie drumsticks together with kitchen string. Place turkey, breast side up, on a rack in a roasting pan. Melt remaining 2 tablespoons butter and brush skin of turkey generously with it. Season skin with additional salt and pepper.
Bake turkey, uncovered, for 3 hours 45 minutes to 4 hours or until thermometer reads 175°F for turkey and 165°F for stuffing, basting occasionally with pan drippings. Cover turkey loosely with foil if browning too quickly. When finished, cover turkey with foil and let stand 20 minutes before removing stuffing and carving.
Bake additional stuffing in pan, covered, for 30-40 minutes. Uncover and bake 10 minutes longer or until lightly browned.