Allow 350-450g per person when buying your turkey, if it is below 4.5kg. With a bigger bird, allow 200-350g per person. Bronze-feathered turkeys don't grow as large as white-feathered ones. Weigh your bird after it has been stuffed. Calculate your cooking times by allowing 45 minutes per kg, plus a final 30 minutes at 180°C/gas mark 4.