The Codebreaker
An All-Purpose Swung Fly.
By Kevin Feenstra

When I was a young angler, I basically stumbled into swinging flies. There was little information available for fly fishing Great Lakes steelhead at the time, so, hoping simply to catch a steelhead on any type of fly, I went to the local library and read. There was a treasure trove of Western books on steelheading, all of which focused on swinging flies. After some trial and error, I caught a few steelhead. My flies were primitive, but when I finally found some other anglers who had swung or stripped streamers for steelhead, they gave me some ideas for what I might tie in order to catch more fish.

They were mostly using attractor flies designed for the Western rivers. These included Green-Butt Skunks, Coal Cars, Rusty Rats, and one peculiar pattern called the Knudson Spider. The spider was developed in the 1930s and quickly became a favorite, at least partially because it was easy to tie. It had a yellow body and a mallard flank collar and tail. I did catch some fish on these classic patterns, including the spider.

However, as I continued to fish every waking moment, I found other patterns that are effective in our region. At first, I used natural sculpin imitations with great success. As time went on, I went through several phases in tying flies for steelhead and other lake-run fish. It was an exciting time, trying new things and learning how fish react to various colors. I found that very flashy patterns had some real benefits and, before long, attractor flies with lots of flash filled my boxes.

Flashy patterns work great, and there are ways to make them effective even during the tough times of winter. However, there are seasons and days when migratory fish just won’t eat attractor flies, especially in cold, slow water. Thus, I increasingly began to use flies that had attractive qualities but were natural enough to tempt fish in cold water. With these natural patterns, it was easier to imitate bottom-dwelling fish such as sculpins, gobies, and darters.

A lot of minnows don’t live on the bottom; rather, they inhabit the realm higher in the water column. These types of fishes can be found almost anywhere in great abundance. Most common among these are shiners, which are a favorite prey of most predatory fishes in the Great Lakes region and beyond. It became my goal to develop a pattern that effectively imitated these quick-moving baitfish that suspend in the water column.

There’s a lot of overlap in my guiding these days. I switch almost seamlessly from smallmouth bass in the summer to migratory fish in the early fall. When guiding for smallmouth, I use a lot of shiner patterns made from craft fur and flash. These work great on the strip-and-pause for smallmouth. However, they aren’t so great on the swing. I liked the materials, but they needed something extra to trigger a strike while swinging. At first I tried adding a Spey hackle to the front. This ploy worked to some degree, but wasn’t great. As time went on, I looked at the old fly patterns for ideas. An idea emerged as I combined the rear half of the craft fur shiner with the front half of the Knudson Spider. The appropriate flash gave the fly some attractive qualities, and the Codebreaker was born.

The Codebreaker goes beyond a winter fly and works any time migratory fish are present. It’s one of the first flies I reach for during fall. It also works well spring and can be modified to catch fish that are gorging on salmon or steelhead fry. As a side benefit, it catches resident fish such as trout, smallmouth, pike, and others. Through fall and winter I tie this fly on a shank of 40 to 55mm. In spring I often tie it on a single up-eye salmon hook to imitate fry.


Shank:  40 to 55mm, up-eye shank

Loop:  50- to 80-pound braid, such as PowerPro, cut into a 9- or 10-inch piece

Glue:  Standard viscosity Zap-a-Gap

Eyes:  Bead chain or lead dumbbell eyes

Tail:  Gray-olive or camel craft fur

Body:  Yellow and shrimp pink Ice Dub or other colors to match local minnows. Other combinations, such as blue/yellow or olive/yellow work great

Hackle:  One or two large mallard flank feathers

Flash:  Flashabou Mirage, gray UV Krystal Flash, and pearl flashabou. Ice blue ripple ice fiber, clear Flashabou, rainbow Krystal Flash, and/or pearl-orange flashabou are other variations that are always in my box


Step 1:   Place the shank in your vise with the eye facing up. Cover the shank with thread from front to back and return to a point one third of the way back from the front eye.

Step 2:   Tie in the eyes. I typically wrap these under the shank. These are optional and not necessary if you are fishing in slow current.

Step 3:   Create a loop by folding the braid in half and tying an overhand knot with the ends. This loop should be 4 to 5 inches long, so you will need to start with 9 or 10 inches of braid.

Step 4:  Thread the loop through the eye of the shank so that it extends 1 inch behind the rear end of the shank. The knot should be below the shank with the loop on the top. Cover the braid with thread and move the thread to the back of the hook. Add a drop of glue if possible. This is the most critical step for durability. If you don’t add the glue, you may get a dramatic strike from a big fish, only to find that you no longer have a hook attached to your fly. Threading the loop this way makes the head of the fly more bulky, but the fly will be bombproof.

Step 5:   Tie in a piece of saltwater Flashabou mirage. If you can find it, iridescent basket shreds are my favorite substitute. You can find this material online or at some craft stores. In my opinion, it’s one of the best non-typical materials for flies. I use it in iridescent color, but also clear blue and clear pink at times.

Step 6:   Move your thread to just behind the eyes. Add some yellow dubbing to your thread and wrap it back to the end of the shank.

Step 7:   Tie in a tail of craft fur about the width of a pencil above the flash. Trim the front of the craft fur but leave a little bump emerging.

Step 8:   Wind your thread in segments back up behind the bead chain or dumbbell eye.

Step 9:  Right behind the eye, tie in a large mallard flank feather. Using your fingers, fold the fibers of the feather backward. Now make a few wraps with the feather behind the eyes. I typically use two feathers on the fly. However, if tying in smaller sizes, I only use one on the front.

Step 10:   Tie in a wing of gray UV Krystal Flash or UV blue Ripple Fiber on top of the hook.

Step 11:   Move your thread in front of the eyes and tie in another large mallard flank by the tip. For now, leave the feather where it is.

Step 12:   Dub the remaining shank in front of the bead chain eyes with shrimp pink dubbing.

Step 13:   Palmer the mallard feather through the pink dubbing, leaving a little room in front to add some flash.

Step 14:   Tie in a pinch of clear or pearl Flashabou twice the length of the fly. Tie half of it in on top of the hook and fold the remaining half under the hook. Lash it down and form the head of the fly.

Step 15:   Finish the fly and attach a trailing hook of your choice onto the loop. For my home waters, I use a Daiichi 2450, size 6 or 4. I work on the Muskegon River, which is big water with constant flow. However, in streams with less current, I use a lighter wire hook to keep the fly on the move.

Kevin Feenstra

In his early 20’s, Kevin began guiding in West Michigan as an alternative to graduate school. Now more than 25 years later, he has never looked back. Kevin’s passion is swinging flies for steelhead and lake run brown trout, but he loves to fly fish for any predator
that swims. He resides in Newaygo, Michigan, guiding many days each year on the Muskegon River System (and fishing whenever he can). The Muskegon is a large and diverse fishery so he guides for migratory fish, resident trout, and warm water species. His steelhead, smallmouth, and trout flies have been published in books, magazines, and online.