Loop Wing Dun
When dressing dun imitations in sizes 16 and smaller, the tyer has a serious challenge: Tying a fly that is close to the weight of the natural. Even the weight of the hook is equal to or greater than the weight of such small insects. So for these small duns I like to use a loop wing that gives a great profile with a minimum of weight.
Bend the front 1/3 of the hook shank upward. Tie in a fan tail, dub on the thorax, and tie in a small clump of poly yarn, mallard flank feather fibers, or any other fibrous material..
Tie in a hackle and wind it X-style over the thorax.
Loop the wing over the thorax and secure it at the head with 3 wraps of thread.
Pull on the butt ends of a few fibers to make smaller loops inside the main loop, then secure the butt end of the wing with several more tight wraps of thread, finish the head in front of the wing butt. Trim the butt ends of the winging fibers to make a short head. Cut the hackle off the bottom of the fly. Place a large drop of thin, flexible head cement on the thread of the head so that it soaks into the base of the wing.