If you can replace expensive, cumbersome, inefficient leaders with something better and less expensive, why not? Leaders are an important part of your tackle. They join your fly line and the fly.
Leaders should have some elasticity, convey energy efficiently, be aero dynamic, provide a drag free drift and obscure your presence from the fish.
For most situations, I recommend leaders made of monofilament. Furled and braided leaders provide no elasticity, do not convey energy efficiently, aren’t aero dynamic, spray water and form an elbow.
All monofilament is not the same. Some is hard and stiff, some is soft and supple.
Hard stiff monofilament provides elasticity, conveys energy efficiently, is aero dynamic, and doesn’t form an elbow, but it drags as soon as it hits the water. Soft supple monofilament doesn’t convey energy efficiently and isn’t aero dynamic, but it drifts beautifully.
Anytime you buy a leader off the rack you’re buying a compromise. It either isn’t stiff and hard enough or it’s too soft and supple. That’s why I build leaders. I want the advantages of both.
A leader is composed of three parts, the butt, (the thick part), the transition (which tapers from thick to thin), and the tippet, (the thin end of the leader). For our purposes, roughly a third, a third and a third.
We identify leaders by their length and the diameter of the tippet. A nine-foot 6x leader is nine feet long; the diameter of the tippet is 6x.
Here is what the x system is all about. X is an unknown variable. If you want to know the strength of your tippet, the unknown variable x is 9. If a leader is 6x, Subtract the 6 from 9 and you get three-pound test. A ten foot, 4x leader is five pound test 2x is 7lb test.,
If you want to know how thick the tippet of a leader is, the unknown variable x is 11. For 6x tippet, subtract the 6, from 11, 5/1000 of an inch, 4x would be 7/1000 2x 9/1000.
With advances in polymer technology, monofilament has become stronger, so the strength aspect of the x formula sometimes isn’t valid, but you get the idea, the larger x value, the finer the tippet.
In most cases you select the size tippet by dividing the hook size of the fly you are using by 3. For example, if I’m fishing a size 18 Henryville Special, I divide 18 by 3 and select a 6x tippet. In very clear water you’re always using 6x or finer, that’s one of the reasons large flies don’t work on leader-shy spring-creek wild trout. There just isn’t enough bulk to a fine tippet to turn over large flies.