Big Backing

[Clay]

Your backing only needs to be stonger than the rest of your set up. Most flylines have a tensile strength of less than 40 lbs. So having 100lb backing isn't going to offer much more real protection than 50 lb. The flyline will give way first, or the leader if weaker than the fly line. There are a few flylines designed for billfish and tuna that test around 70lbs so if you use one of these you might want heavier backing.

Even then you would be hard pressed to apply even 25lbs of pull with a fly rod.even with a 16wt rod. Try it. Rig up a rod, attach the leader to a scale, and see how hard you can pull.

That said, you can get dacron lines up to at least 200lb test. Look for dacron trolling line. You can get spectra braided lines to at least 250lbs.

I'm with you on this. I actually thought that most fly lines had a break strength around 30 pounds so anything stronger than 30 pound dacron for backing and all you are doing is taking up precious space on the spool. If you are after really big fish the deal is not heavier weight backing but more of it. I saw a video (not a lot of saltwater in Wisconsin) of a tarpon fisherman who had 1200 yards of backing on the reel. Big reel, gel spun. Like has been said before, I pass on gel spun. Might as well fish with a chainsaw running next to the reel, that stuff will bite you. If you get it wrapped around a finger on a big fish you are in the big pile if you know what I mean. Salmon I fish with 30 pound dacron. Most stuff 20 lbs and I even have a few spooled up with 12 pound to save on precious reel space on the 3 and 4 wts.

Rick