The Heavy Duck had a slightly thicker barrel than the standard Model 12. To balance the gun, there was approximately 4 ounces of lead in the stock. The barrels were 30 and 32 inch, most were plain or had a solid rib. There were a few with factory vented ribs but they are rare and consequently often faked. The solid winchester pad was standard on the stock with a LOP about a half inch shorter than standard.
