What is PROGRESSIVE ACTION

You see this label on many a rod these days; it has become some sort of a quality mark. In theory, given one certain rod length and one certain line weight, a progressive taper could be just one, definite calculation. Rod people use the term more widely, though. But it is not an "action"; it only says the rod is meant to bend evenly and gradually more up the rod.

As a matter of fact any GOOD rod of any action (with the exception of some "parabolic" tapers, etc, which can´t be classified this way) is engineered to bend progressively, though more or less radical; when the line forces the tip to bend it must deliver this impact down the rod.

Carl i Norgehttp://www.splitcane.se/plugins/system/jcemediabox/img/zoom-img.pngIt has to, otherwise the tip should take all the punch from the cast and, if this is too heavy, be broken. This transition of energy should go down the rod evenly, GRADUALLY loading the rod more and more until it is stopped, preferably in front of the rod grip (the caster´s hand) or under the grip itself. 
Under this pressure the rod fights back the stress in order to regain its straightness, so contributing its part to the cast.

It has to, otherwise the tip should take all the punch from the cast and, if this is too heavy, be broken. This transition of energy should go down the rod evenly, GRADUALLY loading the rod more and more until it is stopped, preferably in front of the rod grip (the caster´s hand) or under the grip itself. 

Under this pressure the rod fights back the stress in order to regain its straightness, so contributing its part to the cast.  The "feel" of the rod bending is commonly called its action, but as I said before, subjectively so.

If a rod bends progressively it uses ALL its length (the "feel" being rapid or slow, according to what action the rod is given).This is a great advantage.
It allows the rod to cast more line weights than a non progressive rod and it will respond better to different casting lengths also;
You have a more resilient rod

If a rod has a weak spot, say in front of the ferrule, You don´t cast a progressive rod. You cast something else but definitely not a progressive rod, a "weak spot" disrupting the EVENLY transported impact.
A rod having a weak portion can be very sweet if You cast the RIGHT line to the RIGHT distance the RIGHT (read "calm" ) day, but be kind of awful if the conditions are altered.
Try another line weight, try to cast at all practical distances on a windy day and You´ll see...

The reasons are obvious, the rod being unable to direct the impact progressively down the rod. The
more pressure the fisherman puts on the rod the weaker this spot reveals to be.
The caster "hits through" the action since the rod cannot respond; it can take an EXACT force only, no more no less.

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American Action Rod

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