The CW Anchor Stone: A Stonefly Built to Get Down Fast

Chris Williamson grew up in the shadow of Mount Rainier and ties in Puyallup, Washington. He started tying in 2020 and says his specialty is probably stoneflies and big, heavy nymphs. The CW Anchor Stone is one of them, built on the Firehole 523 for the moment a fly has to get down fast.

He sent us the pattern the way he wrote it up: the design, how he fishes it, the color range, the recipe and fourteen tying steps. It runs here in his words. After it, a note on the hook.

The CW Anchor Stone

By Chris Williamson

I began tying this pattern in 2021.

I designed this pattern for a favorite stretch of river where fast riffles funnel into small, deep pockets. In these situations, you only have a brief moment to get your fly into the strike zone before it drifts past the target. I wanted a pattern that would sink quickly while still maintaining a natural, lifelike profile.

CW Anchor Stone on the Firehole 523. Photo by Chris Williamson.

This pattern was originally developed to target rainbow trout, coastal cutthroat, and westslope cutthroat throughout the Pacific Northwest. It has since become my go-to anchor nymph on nearly every trout river and tailwater I fish, from the coastal rivers of Washington to the freestone and tailwater fisheries of Montana.

This pattern is effective year-round, with its best performance from spring through fall. It excels in fast pocket water, riffles, runs, and other situations where getting to the bottom quickly is critical.

The combination of materials and carefully balanced weight allows this fly to reach the strike zone quickly without sacrificing movement or a realistic appearance. The soft legs and tails remain lively in the current, giving the fly a natural profile while its weight often eliminates the need for additional split shot.

This pattern was originally designed for Euro nymphing because I wanted a larger anchor-style nymph that would sink quickly while maintaining a realistic profile and natural movement. It didn’t take long, however, before it became one of my favorite indicator flies as well.

My preferred method is fishing it as the anchor fly on a double indicator rig. It quickly gets both flies into the strike zone and keeps the entire rig tracking naturally along the bottom in moving water. It is equally effective on a Euro nymphing setup, where its weight provides excellent contact and sensitivity, allowing you to feel the fly ticking along the bottom while maintaining a natural drift.

Since developing this pattern in 2021, I have extensively tested and refined it on rivers including the Yakima River, Deschutes River, and St. Joe River, as well as many other trout streams throughout Washington, Oregon, Idaho, and Montana.

The color range

Chris ties it in five colors:

• Golden stonefly- golden yellow/brown
• Skwala stonefly- olive/brown
• Summer stonefly- Brown/brown
• Black stonefly- black/charcoal
• Purple attractor stone- purple/purple

Photos by Chris Williamson.

The hook

The 523 is a 3XL jig hook built for stoneflies and crawlers. Heavy wire, 1X gap, a 60-degree down eye, black nickel. A stonefly body wants length, and the 3XL shank gives the Anchor Stone room for a slim abdomen and two distinct thorax segments without crowding the bead.

The jig eye rides the point up, which is what lets a fly this heavy tick along the bottom without living in the rocks. The 523 is a Firehole original, manufactured barbless, in #4 through #14.

The recipe

Chris Williamson's materials, as sent.

• Hook: Firehole 523 3xl jig hook
• Size Range: 14-10 and size 6 for salmonfly version
• Weight: 4.5mm slotted tungsten stone, and I usually apply 8 wraps of .020 lead free wire behind the bead
• Thread: 70-100D gsp
• Barred flexi floss
• Vinyl D rib
• Scud back
• Dirty bug yarn from semperfli
• Ice dub

Tying steps

1. Slide a 4.5 mm tungsten bead onto the hook.
2. Make 8 wraps of .020 lead-free wire directly behind the bead and secure the wire with GSP thread.
3. Tie in the tailing material immediately behind the lead wraps. Secure the material and wrap towards the bend of the Hook to build a smooth, tapered underbody for the abdomen.
4. Tie in the vinyl D-Rib at the rear of the lead wraps. Bind it down along the shank to just ahead of the hook bend and the tail material
5. Add a thin coat of head cement to the abdomen, Wrap the vinyl D-Rib forward in 9 touching wraps towards the rear of the lead wraps. Secure and trim the excess.
6. Tie in the scud skin immediately behind the bead. Bind it rearward to the front edge of the D-Rib abdomen, then lift the material slightly to see if any lead free wire is exposed so we can be certain it will completely cover the lead wraps when pulled forward.
7. Tie in the rear legs using one strand folded in half, creating one leg on each side of the hook.
8. Tie in the Dirty Bug Yarn and make 2–3 wraps to form the first thorax segment.
9. Pull the scud skin tightly over the first thorax segment and secure it behind the bead. Fold the scud skin rearward and bind it tightly against the front of the first thorax segment. This creates a clean separation between the two thorax segments.
10. Tie in the front legs immediately behind the bead and work the excess leg material back towards the first segment creating the middle set of legs leaving enough space for approximately one wrap of yarn or dubbing between the middle legs and the first segment. This spacing keeps all three pairs of legs evenly positioned.
11. Continue wrapping the Dirty Bug Yarn, making one wrap in front of the middle legs and then 3–4 additional wraps to build the second thorax segment, finishing directly behind the bead.
12. Pull the scud skin forward over the second thorax segment and secure it immediately behind the bead.
13. Trim the excess scud skin. Before trimming the thread, apply firm thread tension to pull the remaining scud back tag down between the bead and thorax, hiding the cut end for a clean finish.
14. Form a sparse collar with Ice Dub, whip finish, and apply head cement.

Critical notes: The lead wire must remain completely concealed beneath the scud skin. The abdomen should remain slim and evenly tapered, while the two thorax segments should be distinct and separated by the folded-back scud skin.

The front legs and middle legs can be tied in with 1 piece of material folded and secured

The CW Anchor Stone is also in the Firehole Fly Box. Meet Chris on his ambassador page.

Firehole Sticks 523. Manufactured barbless.

Thank you to Chris for this one.

~John

Sources

• Chris Williamson, CW Anchor Stone write-up, recipe, color range and tying instructions, sent to Firehole, 1 November 2026. Photos by Chris Williamson.
• Chris Williamson, ambassador profile, fireholeoutdoors.com.
• Firehole Sticks 523 product specifications.