First, if your cast results in your leader collapsing into a tangled pile, don't automatically blame the pileup on the leader. First look at your cast. In particular, study your backcast. Does it unroll in a neat, tight loop and straighten out completely prior to reloading for the forward cast? If you can't straighten a name brand, 9-foot leader with a size 14 dry fly at the end, you need to work on your casting. Remember that most leader problems are actually casting problems. That's good news because you can learn to cast well enough to make a reasonably good leader turn over. Efficient casting also lets you make a leader do tricky things, such as landing with slack in it or curving off to one side.
Leaders have three parts. The thicker end, which is tied to the fly line, is called the butt section and should take up at least a third of the leader's total length. These butt sections are measured in thousandths of an inch: 0.021, 0.022, or whatever. Most trout fishing leaders have butt sections from 0.019 to 0.023 in diameter.
The middle of the leader is called the mid-section or tapered section. This is where the leader's diameter decreases rapidly. This mid-section should constitute 25% of the leader's total length. In that short distance (two to three feet), the diameter of the line drops from, say 0.021 inches at the butt to 0.008 or smaller at the tippet end of the mid-section.
The end section of the leader is called the tippet and is the business end of the entire fly line where you attach the fly. We Americans, describe tippets with a X system, which has nothing to do with breaking strength. But the X system does tell you the thickness of a tippet. It's called the Rule of 11. Subtract the X number from 11, and the result is the material's diameter in thousandths of an inch. A 4X tippet, then has a diameter of 0.007: 11 minus 4 equals 7.
The three most common lengths for knotless trout-fishing leaders are 71/2, 9, and 12 feet. All things being equal, a shorter leader is easier to turn over than a longer one. So, you should use a 71/2 footer, right? Not necessarily. For one thing, the greater the distance between the fly line and the fly, the more likely a fish is to take the offering. And a longer leader presents a fly more delicately and allows for a longer and better drift.
So, should you use the 12 foot leader? Well, it depends. Can you get it to turn over and straighten out completely today, at your present level of casting skill? Even the best leader won't do you any good if the cast ends in a tangled mess. Do not doubt that you can learn to make perfect presentations with a 12 foot (or longer) leader. But if you can't cast well enough to do that today-be honest, now---use a 9 foot leader.
Length of leaders will also be determined by the fly itself. You'll probably find a big Marabou Muddler easier to throw with a 71/2 foot leader than with a 12-footer. Dry flies don't weigh anything, but a big, bushy one can have considerable wind resistance. You'll find a fluffy dry fly easier to cast with a 9-foot leader than with something a lot longer.
But while a shorter leader can make for easier casting with a streamer, it might not make for better fishing. With a floating line, a streamer or wet fly will swim deeper on a 9-foot leader than on a 71/2-footer. Take your pick: a shorter leader might make a weighted fly easier to cast, but a longer leader will let you reach the same depth with less weight. A heavier outfit-a 6-weight instead of a 4-weight---lets you use a longer leader with a heavy fly.
You can also match the leader to the water your fishing. On a fast section of a narrow brook hemmed in by shrubbery, you're not going to make long casts. With a shorter leader, you'll have more fly line in the air to load the rod. Here, use a 71/2-footer. But on a calm pool in a midsize river, you want a long leader; try the 12-footer.
By and large, 9 feet is the most versatile and manageable length for trout fishing. It's long enough for most dry-fly, wet and nymph fishing on most streams, and short enough for throwing the streamers and large nymphs. By adding a few feet of tippet material, you can stretch it to 10 feet or so for the more delicate requirements.
But also realize this, if you can add material to lengthen a leader when the conditions demand, than you can also cut the longer leader to a size shorter to solve your next fishing problem.
A loop to loop connection between the fly line and leader allows you to replace a leader without having to tie knots. Most tackle shops sell braided loops for the ends of fly lines. Or you can double the tip of the fly line to make a 3/8-inch loop and secure it with two nail knots tied with 8-pound monofilament. Tie a small perfection loop in the butt end of the leader, and join the line and leader by interlocking the loops. To change leaders, simply undo the connection.
The longer and finer the tippet, the more bites you'll get. That's true with pretty much any type of fly. The problem, sometimes, is getting a long, skinny tippet to turn over.
To help solve this problem, you need to understand another relationship and that's between the size of a fly and the tippet. A dry fly won't travel far under it's own momentum; your leader and tippet have to carry the fly almost all the way to its destination. With most dry flies, you can divide the flies hook size by three to get a rough idea of the right tippet diameter. For instance: with a size 12 dry fly, a 3X or 4X tippet; with a size 14 fly, 4X or 5X; size 16, 5X or 6X; size 18 and 20, 6X or 7X will do the trick with a tippet length of at least 2 feet.
With wet flies and most nymphs, you can use a lighter tippet than you would with a dry fly of the same size. Remember, you don't have to turn-over a size 12 Gold-Ribbed Hare's Ear nymph. Once that dense, streamlined fly is moving at mack-1, it will sail to its destination without much help. I've long used 5X tippets for nearly all wet and nymph flies sized 8 down to size 14, and 6X for size 16 and smaller. Here, too, use about 24 inches of tippet material.
A streamer in motion also sails pretty well. I hardly ever go heavier than 3X with a streamer. With smaller streamers, I use 4 and even 5X tippets. The lighter the tippet is, the better a fly's action will be. You do however; need to produce a fair amount of line speed, which comes not from a mighty heave, but from longer casting planes that, accelerate smoothly.
Knotless leaders taper almost imperceptibly, which can make it tough to know when to add tippet. Try this method. Take your new 9-footer, 4X leader, measure back 24 inches from the tip, and cut it there. Tie on a piece of 4X tippet material with a double surgeons knot. The knot becomes a marker; it lets you see that the tippet is getting short. When you need a new tippet, cut back the 4X material to a length of about 6 inches, and tie the fresh tippet to that. If you want a longer finer leader, cut the 4X material back to about 12 inches, and add 24 inches of 5X. If you need to shorten the leader, well the spot to cut is already marked for you.
In time, with a bit more experience, you'll have several different leaders located in a leader wallet that fits in a pocket of your vest. You can experiment with lengths, materials, and taper designs.
The endless tinkering is part of the fun of fly-fishing. And you will need more than one leader. For most of your trout fishing, though, a small simple assortment of leaders and tippet material will do the job. The main thing is to use a leader well. Perfect your casting first, and then worry about making tiny adjustments in the taper of a 12-foot leader.
When the time comes that you would like to make your own leaders, here's how. The key to such "roll your own" leader construction and modification lies in knowing how to tie only three knots. These knots have been known to cause grave cases of frustration and despair, but the easy-to-learn, three-turn Surgeon's Knot has a less-dire prognosis. The Surgeon's knot is little more than a fancy overhand knot. To attach a tippet to a leader, for example, begin by overlapping the ends of two pieces of material.
Be certain that you overlap enough material so that you can tie the knot with ease. Now, form an overhand knot in the middle of the two pieces. As you do so, be sure that the two loops of line (leader and tippet together) formed by the overhand knot are equal in diameter. Take the long (or "standing") end of the tippet material and the short (or "tag") end of the leader through the knot three times. Lubricate the knot with water or saliva, and then simultaneously pull all four ends smoothly and thoroughly to tighten the knot. Pull hard enough to make certain that the knot is fully formed and will not slip if pressure-perhaps from a fish-is applied. Cut the tag ends close to the knot to prevent excessive hang-ups on weeds, algae, and other obstructions. That's it, one three-turn Surgeon's Knot.
With this knot you can build an entire leader or simply add a new section to a pre-made leader. There are a plethora of leader formulae out there, as well as principles that can help you understand how to design your own leaders. To get you going, I have included two basic formulae below-one for dries and one for nymphs-that can be made using nothing but a three-turn Surgeon's Knot and leader material that you can get at any fly shop.
Note
These leaders are designed for a 5-weight line. Material sizes are shown in thousandths of an inch, with any corresponding "X" designation shown in parentheses. Remember to use enough extra material when attaching each section so that you can tie the Surgeon's Knot with ease.
Dry Fly Leader
Start with 4 feet of .021, then add 1 foot of .015, then add 1 foot of .011 (0X), then add 2 feet of .008 (3X), then add 1 or 2 feet of .007 (4X) or .006 (5X).