Fly line weights. My opinion on the subject

AFTM numbers are more of a set of guidelines, rather than actual rules.

The most important thing to consider with line weights is that the purpose of line weight, is the loading of the rod.
The delicacy of the cast, or the disturbance of the surface film, are secondary to the pure mechanics of loading the rod to perform the cast. If you get that right, then you can drop your fly as delicately as thistledown and still catch fish.

There is a growing, and in some respects understandable, fashion for ultra light fishing. AFTM numbers all the way down to one are all very well, but need to be considered as a whole, and not just as lighter is better. This is most particularly important when considering bamboo rods, which are entirely different from carbon and while the discipline of fly fishing remains the same, the engineering and experience are very different and I will try to explain why it is not sensible to over obsess about light line weights.

Last week I had a first trial of a new fly line (new to me, not new to market), and while messing about a friend handed me a new Snowbee carbon rod. I have not handled a carbon rod in at least five years and I had forgotten how they feel, but I can not fault the rod for its quality or the casts I was making with very little effort or adjustment time. I must however comment on this, it was absolutely arrow straight, perfectly balanced and completely dead in the hand, perhaps a more flattering word would be neutral, but I could feel nothing of the rods life until the line loaded the blank on the back cast. Bamboo is a very different thing, with the life of the rod present, even at rest you can feel the fibres flexing, it is like holding a living thing in your hand.

So what has this got to do with line weights? I’m getting around to that. A ‘neutral’ carbon blank transmits feeling to the hand when it has a load on it, and with the action designs that load happens quickly and quite late, as the term fast actioned rod implies, so a three wight line will transmit the feel of a 7” trout, and therefore enhance the enjoyment of the sport far better than a five weight, for example. Bamboo on the other hand is a much more progressive material, and every knock at the tip will be felt in the grip, so the sporting element is greatly enhanced for a given line weight. Now to the practical, bamboo, being softer of action also needs more backbone to handle a fish, and while I’m all for good sport, I would consider it irresponsible for us to fish so light as to have to completely exhaust a fish in order to control it to the net or hand. In most cases AFTM four in bamboo is as light as we should really be fishing, if we are tackling chalk stream fish, which can regularly top 2lbs, then I would say AFTM five or even six are more sensible options. I consider the #3 weight Garrison 201 to be the absolute limit and I always opt for my #5 weight Dart when I’m on the moor chasing wild fish in what is most often a head wind. I had a 28 fish afternoon on the #5 weight so line weight isn’t an obstacle to catching wild fish.

If concerned about the disturbance heavier lines create then I really recommend using silk lines, which have about 50-70% the diameter of the equivalent PVC line, or (and this is what I am trialling this season) the Snowbee Thistledown lines. There are a few manufacturers of synthetic alternatives to silk, so I’m sure there are other options, but I’m sticking to experimenting with the one for now. My initial impressions are that it is a good alternative to silk, but until I have put in some serious hours on wild fish I will not be able to say more.

To conclude my ramble, do not consider bamboo rods and their carbon equivalents as comparable when it comes to line weights. Consider the fish you will be targeting and the water you will need to cover and remember that we have a responsibility to care for the welfare of our quarry above all else. The tackle needs to do the job properly, if you are honest with yourself and you are willing to listen to the experience of people who have extensively researched their art then you will get a lot more from the right rod and line, than you will from the fashionable.