Still a relative newbie to fly fishing and maybe i should have figured this one out by now but i haven't so now want to get a better understanding of what type of leader to use in which circumstance assuming you have both in your bag which would you use for :
Sinking line - weighted fly
Sinking line - booby
Floating line - weighted fly
Floating line - unweighted fly
Floating line - Dry fly
etc
or doesn't it really matter that much ?
Just my tuppenceworth...
...
First rule of leader club...
It
can matter that much... sometimes...
Preamble - for this purpose, I need to assume that you agree that for stillwater dry fly fishing, you want to have your fly floating but your leader under the surface. I'm just going to take that as a gimme. OK, let's carry on...
Second rule of leader club... the alternative to fluorocarbon is
nylon, not copolymer. Copolymer is marketing-speak for nylon. Fluorocarbon and nylon are comparable materials with different properties, 'Copolymer' is nonsensical in this respect.
It's when to use
nylon and when to use
fluorocarbon.
Third rule of leader club...
Water has a density of 1.00
Nylon has a density of 1.05 to 1.10
Fluorocarbon has a density of 1.75 to 1.90
If you hold a piece of nylon and a piece of fluorocarbon (of similar length and diameter) just below the surface and let them go, the fluorocarbon will sink at 3 times the rate of the nylon. This difference
greatly affects how your flies fish, particularly when slow-fishing lightweight flies in stillwaters. Ask any expert at the 'washing-line' technique, or those who swing buzzers on the dead drift.
Fourth rule of leader club...
While fluoro sinks at 3 times the rate of nylon, there is an interfering factor: the surface interface. This is the bit between air and water. It is highly water-repellent, so is in turn highly attractive to anything else that is water-repellent. This includes leader materials, in particular fluorocarbon. So, while it might seem a better idea to use fluorocarbon to get a dry-fly leader to cut through the surface, the extra density is trumped by its greater water-repellency. So, if you want to fish stillwater dries
and get the leader below surface, you are better with nylon.
Fifth rule of leader club...
Not all nylons and fluorocarbons are the same. In both camps, there are materials that have been messed about with. Some call them 'pre-stretched'. Some call them 'low-diameter'. Some call them 'double-strength'. What they bring to the table is extra breaking strength for the same diameter... but at a cost. They are more brittle than the standard types - less able to resist sudden shocks or abrasion. However, with practiced use, they can and do outperform standard materials when a 'high-performance' is required. The trick is in knowing when to use them.
Sixth rule of leader club. Ignore all received wisdom about visibility of fluorocarbon and nylon below water. Accept they are different at different times, and it can make all the difference as to which you are using on the day.
So, what I would use with your list...
Sinking line - weighted fly ... Depends what I am trying to do... speed of sink of the line, amount of weight on the fly, speed of retrieve, depth I am trying to fish it at... either nylon or fluorocarbon.
Sinking line - booby ... Depends on things like rate of sink of the fly line, the size of the booby eyes, the speed of retrieve and the depth I am trying to fish the fly at... either nylon or fluorocarbon.
Floating line - weighted fly ... Depends on how much weight, what length leader, what speed of retrieve, etc... either nylon or fluorocarbon.
Floating line - unweighted fly ... Depends on what depth I am trying to fish the fly at... either nylon or fluorocarbon.
Floating line - Dry fly. Simples! Nylon.
And if I am catching nothing while my boat partner is hauling them out, and we are on different materials, then I will change to what he is using...
Col
...it's always going to get opposing views
