One of the main advantages of constructing your own lines for winter steelheading, especially for accomplished casters, is that you can modify the belly section of your main line to suit your needs.

There are many long-casting lines out there, but many are of a weight-forward design, with a lot of thin running line that follows the head after a "shooting" cast. When I fish big water in the winter, and need to make long casts, I avoid shooting line because first I have to retrieve all that line, which is very inefficient and makes for cold hands and frozen, icy guides.

Because running line is thin, and has very little mass, it makes a very poor conductor of casting energy. In fact, as soon as you have running line extending from your tip-top, you will find that your ability to aerialize the cast, or mend the line--in the air or on the water--deteriorates rapidly.

Long Belly = Good Line Control Because it is difficult to transfer energy from your rod tip through a thin running line, long-belly lines are most effective for winter steelheading.

In order to aerialize a long cast, roll or Spey cast, or throw the big mends required for winter steelheading, the head of the fly line should be in direct contact with the tip of your rod. As a rule of thumb, the head length of your winter steelheading line should equal the maximum length of line a you can comfortably carry in the air. If you can buy a line off-the-shelf that meets these requirements, there is no need to extend the belly.

Since many commercial lines (especially Spey lines) have bellies that are too short for effective presentation and line control at the distances I fish, I modify my lines by adding several feet of level line of an appropriate weight to the rear of the belly. I prefer to insert this additional line in the rear of the belly because some Spey lines have custom tapers built into the forward part of the belly; if you cut into this section of the line without a clear understanding of what you are doing, you could destroy the casting qualities of your line.

As a rule of thumb, the head length of your winter steelheading line should equal the maximum length of line a you can comfortably carry in the air.

To add line to the back of the belly, first find the rear taper of the line. You'll want to add the extra piece to the level section in front of that taper. Next, use a micrometer to check the thickness of your original line in the area you intend to cut, and select an additional length of line that will match it. After you've made you cuts, and attached kevlar loops using the method I described in the previous section, add the extra belly section using loop-to-loop connections.

Judging the correct amount of additional belly will require a little experimentation and estimation, as you'll have to first determine your desired casting distance, calculate the present average length of your head (which will include the attached sinking-tip, the belly, and the rear taper), and then figure out how much belly you want to add. I wouldn't recommend adding any more than 10 feet to start, as you'll want to be very careful that you don't overload your rod. After test-casting your new line you can cut down that extra section and put new loops back on if you've added too much line.

While I admit that lengthening a factory line can be a rather fiddly process, the results are worth it. A friend of mine who is an accomplished Spey caster, fishes an 18-foot rod for steelhead in Washington and British Columbia. Other than the rather inefficient traditional long-bellied double taper lines, he couldn't find a Spey line suited to this rod--the lines were all too short. He solved his problem by adding ten feet of level line to the back of his factory Spey line. This change allows him to cast long distances without shooting much line, and gives him additional control while mending as there is more belly and less running line between him and the fly. This new line proved its worth on the Skykomish River last spring when he hooked an acrobatic 15-pound chromer on a long, carefully controlled cast to water I'd already covered with a less effective system.