Game Anglers Instructors Association
Andy Grey Fly Fishing

Fly fishing lessons, guiding and casting instruction in the heart of the Cotswolds

Pike Fly Fishing
Carp on the Fly
Make your cast Crackle and Pop with SNAPP

Reams and reams has been written about fly casting, my bookshelf groans under the weight of hefty tomes packed with all manner of advice and instruction on how to make the ‘perfect cast’. Read them all and I guarantee that your head will end up spinning with seeming contradictory advice and differing principles aimed at helping you achieve the ideal technique to get you fly out to a fish.
There are of course many ways to skin a cat, but one thing that they all (pretty much…) agree on are the 5 Essentials for a good cast. If you learn, understand and put these into practice then you will be well along the road to being a better caster, and we all know better casters catch more fish!
So, what are these 5 magical rules? Well, think SNAPP!
S – Straight line rod tip path.
N – No Slack line
A – Smooth Acceleration to a Controlled Stop
P – Pause!
P – Appropriate Power application
So, lets get into the bones of these 5…
Straight Line Rod Tip Path
Straight lines are good. They are efficient and the best use of energy. Think hitting a snooker ball with a cue. Lovely efficient, accurate straight-line transfer of energy. Everything working in the same direction without wasting energy by going round corners or deviating from a straight line path. We want our cast to go out straight ahead of us, traveling in as straight a line as possible (you may have now noticed my liking of the term ‘straight’ by now).
If the rod-tip travels in a straight line path, so will the line.
No Slack Line
Good fly casting is all about efficient transfer of energy. We are trying to transfer energy from our hand via the rod into the line. We are putting tension – which is essentially energy – into the line. A slack or partially slack-line cannot be put under as much tension over it’s full length as a non-slack line and therefore cannot be energised as efficiently.
Eliminate slack from the line and you will be able to put more energy into your cast making it more efficient.
Smooth Acceleration to a Controlled Stop
As the previous rule, we are trying to put energy into the line. Now, lines left to their own devices are essentially bits of limp string. Once we start to accelerate the line at the start of the casting stroke we need to constantly maintain and increase that tension. If we slow down during the casting stroke then tension will be lost and we’ll end up with Slack Line (which by now we know is a BAD THING).
So we need to be constantly accelerating the rod-tip through the casting stroke until we make a Controlled Stop.
‘Controlled’? Well, we used to say ‘Abrupt’, like you where hitting a wall, but this can lead to problems in itself and as we should be aiming to be in control of our casting let’s settle on ‘Crisp’ for now, but you get the idea.
Why? Well, we have our smoothly accelerating rod-tip travelling in a nice straight path with that lovely slack-free line full of energy. We then need to let it go – think throwing a ball. Stop the rod crisply and the line then travels over the rod tip following its straight line path to the target.
Big explanation mark behind this one. This takes us back to the No Slack line thingy. Our line is now unfurling either ahead or behind us (depending if you are making a forward or back-cast) If we immediately start the next casting stroke without pausing then the line will not have straightened out enough to enable us to put tension into it. Put simply you can’t push string.
The timing of the pause is dependant on the amount of line being cast. Short line- short pause, long line – long pause.
Appropriate Power Application
Bit of a catch-all this one.
In order for us to achieve a Straight Line rod tip path we need to match the power and the arc of the casting stroke to the length of line being cast. Too little power and too great a casting arc and the rod will not flex enough to flatten the tip-path resulting in a convex tip-path and a big open loop. Nasty.
Too much power and too little casting stroke will give you a completely concave tip path. This has its uses but let’s not go there just yet… Suffice to say it’s not what we are after.
An uneven power application (basically back to our smooth acceleration rule) equals a rod tip moving above and below the ideal straight line path resulting in a  corresponding wave in the fly line and Tailing loops, which will send you to eternal casting purgatory.
Power and casting arc matched to the length of line outside the rod-tip = straight line rod-tip path = a neat efficient cast.
Now just to confuse things it is possible to have a nice straight line tip-path but apply more power than can be dispersed by the line and leader. This will result in the leader kicking back at the end of the cast, great for some of the more esoteric presentation casts but if you are after a nice smooth presentation of your fly you want to put just enough energy into the line so that it runs out as the leader turns over.