I'm running 20# fireline on my spinning reel.  It is so visible I am sure I need a leader.  I have just tied on some 12# Cajun red to a small barrel swivel and tied the braid to the swivel.  I made the leader about 20 inches long.  There must be some balance between leader length, casting difficulty, strength and visibility.

I am mostly casting 3/16 to 1/4 ounce lures.  So far, casting distance seems low.  I switched to the braid to help with hook sets with a ml 6'6" fast action rod.  That part seems to have helped as I've lost fewer fish.

Suggestions on a leader?

First off, 20# seems pretty stout for most spinning applications. It has been my experience that 8# or 10# fireline/braid is more than I will ever need (more is not warranted as 10# fireline will overpower about any normal bass spinning rod).  I suspect this is why your casting isn't as good as you had hoped.  I have found that nothing I have used will out cast 8# powerpro.

As far as your question is concerned: I have had super luck with 3 to 4 feet of Flourocarbon as a leader tied on with a back to back uni knot. With this knot you can wind it right through the guides and cast with no problem..........so if the water is clear I will go with up to 8ft and still cast with no problem. Normally though 4 ft will be plenty IMHO. I like the Berkely Tournament 100% flouro, tried a few and this is my favorite for knot strength and easy availability.

matt

I use 10# PP and 20# mono leader with swivel about 18", works fine.

Use P - Line CFX fluorocarbon leader, 10 or 12 pound.

I'm running 20# fireline on my spinning reel. It is so visible I am sure I need a leader. I have just tied on some 12# Cajun red to a small barrel swivel and tied the braid to the swivel. I made the leader about 20 inches long. There must be some balance between leader length, casting difficulty, strength and visibility.

I am mostly casting 3/16 to 1/4 ounce lures. So far, casting distance seems low. I switched to the braid to help with hook sets with a ml 6'6" fast action rod. That part seems to have helped as I've lost fewer fish.

Suggestions on a leader?

Fireline is a fused line, not a braid. I used 14# on spinning for about three years and had no complaints other than lack of casting distance; the line just didn't seem to flow off the spool smoothly.

I tried 15# Power Pro and that casts much better than the Fireline did. I never used a leader with either line, but that's not a recommendation, just one of my personal habits.