Not a bug, a very poorly designed system. As wataru stated it is in propItemEtc.inc. Look for the item id and remove some of the attributes to remove lines from that weapon. If it isn't there, find one of the attribute ID's and look in all your resource files for matching id's that related to that item. If all else fails, it will be in either propitem.txt or spec_item.txt (depending on source/resource version)