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Trout Spey : Fly lines

The development of fly lines is central to the evolution of Trout Spey. I begin by discussing the three main line options: Skagit, Scandi and hybrid, then consider integrated lines versus separate head and running line systems, and finally touch on the implications of running line choice on reel selection.


Skagit Heads

Skagit heads are short fat shooting heads with sufficient grains per foot to lift heavy sink tips intended to be part of the head system. Tips of varying length and density are attached to the head via loop-to-loop connections.


Standard steelhead and salmon Skagit heads are between 20 and 25 ft long, and weigh in excess of 400 grains.

In 2015, micro- Skagit heads of 11-16 ft and 150-360 grains entered the market. Micro-Skagit heads are arguably the most versatile lines available to the Trout Spey angler.

After two years, 2017-19, of experimenting with every series of micro-Skagit head produced between 2015 and 2020 by the leading fly line manufacturers (OPST, RIO, Airflo, Scientific Anglers), I found that one or two feet in head length makes a huge difference in performance.

Longer heads of a particular weight had less lifting power, but were capable of greater distance and better presentation, and did not require as much stripping, which is an advantage when swinging flies, but a disadvantage when stripping streamers.

To cast heavy tips of 9-10 ft I found that a Skagit head should be no longer than 1.25-1.4 times the length of the rod. Heavy tips are approximately 30-50% of the head weight and usually made of level-T material. For light tips of 10 feet, usually coated leaders or Rio Replacement Tips, the ideal head length was 1.6 - 1.7 times the length of the rod.

In addition to total length, the front taper also influenced Skagit head performance. Heads with long gradual front tapers, culminating in thick tips, generally performed best. They were easier to cast and achieved better distance and presentation for a given head length, without sacrificing lifting power.

The ultimate Skagit head for casting heavy sink tips on 9-9.5 ft 5 wt single-handed rods was, in my experience, the 11.3 ft Scientific Anglers 185 grain Skagit Lite. With this head I could easily cast heavily weighted 3 inch rabbit streamers using a Rio S3/S4/S5 3D MOW light tip, a 10 ft Airflo T-7 Flo Tip and 9 ft of T-8 and T-11. Rio 10 ft #6 Replacement Tips worked extremely well for lighter flies.

The best Skagit head for casting light tips on 9-9.5 ft 5 wt rods was a 15 ft 186 grain Airflo Skagit Scout. Although this head could not manage much more than 7.5 ft of T-8, when I attached a 10 ft #5 Rio Replacement Tip, it turned into a 2-D Hybrid head, capable of laser loops and phenomenal distance and presentation with moderately weighted streamers.

To maintain rod length to head length ratios, longer rods require longer heads. A 15.5 ft Skagit Scout 300 was therefore ideal for casting heavy tips on my 4wt 11.25 ft double-handed rod.


Although floating Skagit heads are more versatile, intermediate Skagit heads have advantages in certain situations. The first intermediate sink micro-Skagit head was manufactured by Scientific Anglers in 2019.


The advantages of intermediate heads are, they:
1. slice through wind,
2. make less splash,

3. achieve more depth with a tip of given weight,

4. remain at depth throughout the swing, including when animated or stripped upstream,

5. are less impacted by surface currents, and

6. result in a slower swing, often necessary for tempting winter fish.

Since floating micro-Skagit heads are affected by strong wind, and there's a limit to how much weight they can cast, intermediate heads substantially increase reach for the Trout Spey angler.

Choosing the right weight and length of sink tip for a particular rod and head is critical for casting success - too heavy or too light, too long or too short, and it ends in tears. For more on this complex topic, including some winning formulae, check out my article, ‘Sink Tips for Skagit Heads'.


Scandi Heads

Scandi heads are much longer than Skagit heads and they have long fine front tapers. They are usually around 2.6 to 3 times the length of the rod, with a front taper 4 times the length of the belly, and are typically 27-34 ft long in Trout Spey sizes.

Designed for delicate presentation with light flies, Scandi heads don't handle wind or sink tips in trout sizes.

For Trout Spey applications, Scandi heads are useful for delicate presentations with soft hackles and dry flies on outfits using heads of 270 grains or greater. For lighter outfits, hybrid heads are sufficiently delicate and more versatile.

Scandi heads suitable for Trout Spey include the Rio Single Hand Spey and Scientific Anglers Trout Creek for single hand rods, and the Rio Scandi Short and Airflo Rage for double handers. Since these heads are made for 'touch and go' casts, they are usually used 30-50 grains lighter than the Skagit head used on the same rod.


Hybrid aka Scandit Heads

Hybrid heads, aka Scandit heads, may be thought of as very short Scandi heads with slightly thicker tips. They are more graceful than a Skagit, but have more power than a Scandi to handle wind and heavier tips and flies. They excel at both Touch and Go and Sustained Anchor casts.

For those interested in numbers, hybrid heads are 2-2.4 times a rod's length, with a front taper of 1.3 to 2.5 times the belly. In Trout Spey grain weights they are usually 20 - 23 ft long.

Hybrid heads less that 250 grains work well with tapered leaders and Polyleaders (5 ft for single handed and 10 ft for double handed rods), and are great for swinging soft hackles and dry flies, and fishing small weighted streamers and nymphs.

Hybrid heads of 265 - 325 grains work well with Polyleaders and Rio Replacement tips (#5 or #6 depending on head weight), and are ideal for fishing moderately weighted streamers on wide rivers during summer and autumn.

Excellent examples of hybrid heads for trout include: the Scientific Anglers Scandi Lite (20-27 ft), the Rio Trout Spey (22 ft) and Rio Scandi Body (23 ft).


Excellent hybrid heads for single hand rods are the 150 grain Scandi Lite for standard 9 ft 5 wt rods, and the Scandi Lite 180 or Rio Trout Spey 190 for powerful 5 wt and 6 wt rods.

When it comes to Hybrid heads for 4wt and 5 wt two-handed rods, I found the 23 ft Rio Scandi Body in 300 to 400 grains to be so effective I have not bothered testing anything else.


Integrated versus Head Only

All three types of Trout Spey fly line discussed above are available as just the head portion (termed ‘head only’), which is then attached to a separate running line by means of a loop to loop connection; or as a continuous (‘integrated’) fly line, i.e. with the head permanently attached to a running line made out of the same material as the head itself.

Nylon monofilament running lines are generally regarded as the best type of running line for head-only Trout Spey lines, because they provide the greatest distance with light shooting heads. They also offer advantages for mending and line control.

Mono running lines are not all made equal though, as they come in a wide range of profiles, diameters, breaking strain, stiffness and propensity to coil. For more about choosing a mono running line see my article,‘Single Hand Skagit: Science behind the magic'.


The first integrated micro Skagit and Hybrid heads were produced by Scientific Anglers in 2017 as part of their Spey Lite series. These were followed by the OPST Commando Smooth (Skagit) and Rio Trout Spey (Hybrid) and Skagit Trout Spey in mid-2018.

The advantage of a continuous fly line is that one doesn’t feel the click of loop -to-loop connections passing through the rod guides when stripping close, and the running line is easier for inexperienced anglers to handle. Short casts made without the head completely out of the tip eye are also a little less clunky.

Disadvantages of integrated systems are: 1) they do not cast as far as heads on mono running lines; 2) one cannot hold 20-30 feet of running off the water to avoid drag without disturbing the head; 3) one cannot change heads without changing spools/reels; and 4) they are almost twice the price.


Integrated Skagit systems appear to be best suited for smaller waters where distance is not an issue and stripping really close is frequently necessary. They may also be a better choice for anglers transitioning to the world of Spey who want to initially keep new variables to a minimum.

From the start, I had no problem using mono running lines, and I am not a fan of integrated systems for Skagit heads light enough for 5wt rods. I love the silky-smooth deft casting of a light Skagit head on a thin mono running line, and I rarely need to retrieve short Skagit heads through the rod tip.

Integrated Scandi systems are a different story.


They are especially useful for catching high numbers of large trout, such as during the evening caddis hatch on the Tongariro. In this scenario, the running line to head connection does not stick in the guides as it moves in and out of the rod tip whilst fighting strong fish, which is not only annoying but also results in break-offs.


Although integrated Scandi heads do not cast as far as Scandi heads on mono running lines, distance is seldom an issue when fishing soft hackles or swinging dries. Accuracy and ability to control speed of the drift and swing are much more important.

Reels and running lines

Choice of running line influences reel selection.


When using thin mono running lines it's a good idea to use a full cage reel to avoid the line squeezing between the spool and reduced frame - know as 'pull through'.

Since integrated head systems have thicker coated running lines, they do not require full cage reels, but do require more space and, hence, a larger reel.

Large arbours reduce coiling of both running lines and heads. Increasing the rate of line retrieval also helps when getting rid of loose running line when a fish is hooked - especially when stripping flies - or when a fish turns and swims toward the angler.

Heavier reels are generally required to balance longer rods.

The following reels are ideal for Trout Spey applications with mono running lines:

1. Rods 9 ft or less and head weights 150 - 180 grains - Danielsson L3W 2six and Sage Trout 4/5/6.

2. Rods 9-10.3 ft and head weights of 180 - 250 grains - Danielsson L3W 4seven and Sage Trout Spey 1/2/3.

3. Rods 11-12 ft and head weights 250 - 400 grains - Sage Trout Spey 3/4/5 or Danielsson L5W 6nine

What is Trout Spey

+ How it all began
+ What is Spey casting?
+ Fly lines
+ Sink Tips for Skagit Heads
+ Single versus two handed rods
+ Favourite Trout Spey outfits
+ Conclusions

Single Hand Skagit - Science behind the magic

+ Where it all began
+ Head design
+ Sink tips
+ Casting heavy sink tips
+ Running lines
+ Reels
+ Rods
+ Intermediate heads
+ Favourite outfits
+ Conclusions
+ Casting Notes for 12 Skagit Heads I tested
+ Table of Sink Tip Recommendations
+ Table of Lengths and Weights of Sink Tips

Single hand Trout Spey : Getting started with a 9 ft 5wt rod

+ Getting started
+ Rods and Skagit heads
+ Sink tips for Skagit heads
+ Tippet for Skagit heads

Intermediate Skagit heads

+ Hybrid heads
+ Floating tips for Skagit heads
+ Running lines
+ Cost effective approach
+ Learning to Spey cast
+ A final word

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