Like a Nesco roaster? I have them in four sizes and use them all the time. The website is a godsend, here's the link...
http://www.nesco.com/recipes/?season[]=600&submit=recipe&uid=21
and copy/pasted:
"How to Roast Turkey
One 14 to 22 pound turkey, fresh or frozen
Poultry seasoning
Salt
Pepper
1/4 cup butter or margarine, melted
1 teaspoon browning sauce such as Kitchen Bouquet®(optional)
Preheat 18 quart Nesco® Roaster Oven to 400º F. If you have a 12 quart Nesco®, a maximum 14 pound turkey is recommended. Cooking times (per pound) remain the same.
Clean and rinse turkey. Pat dry. Remove neck and giblets. If desired, prepare separately. Place turkey on rack. Use a pastry brush to spread mixture of butter and browning sauce evenly over turkey skin. Season with poultry seasoning, salt and pepper.
Determine length of roasting time, normally 15 to 20 minutes per pound. A stuffed turkey will add 30 to 45 minutes to total roasting time.
Stuff cavity, if desired. Cover. Roast one hour at 400º F. With baster, remove any liquid and fat from cavity of bird and cookwell. Set aside to make gravy. Brush bird with basting liquid or butter mixture.
Reduce temperature to 350º F. Roast for remainder of cooking time. Use baster, to remove any liquid from cavity of bird and from cookwell when cooking time is about half-way through. If dry, baste turkey with basting liquids.
If turkey isn't as brown as you like it, increase temperature to 400º F. Roast remaining portion of time.
Use lift handles to remove turkey. Be careful - rack will be hot. Set turkey on a platter or cutting board. Let stand 10 minutes before slicing.
If turkey is done early, reduce temperature to 200º F. until serving time."
I've cooked all sorts of meats in my nesco, have never used a bag (I would be afraid of it melting up against the sides), and it always turns out fine.
Good luck!
Terri