After my last post on fishing high water for trout where I speak about using heavier than flies to get into the feeding zones, I was asked about how exactly I go about casting heavy flies.

I had to think about it but couldn’t give a clear answer to what seemed like a very simple question. So while in the Cederberg I made a point of casting a few heavy flies on both a #3 and #5 and paid attention to what I did differently. Because it does require a change!

An old photo from early days on the Jan du Toit. I'd like to say that is planned but it is actually a good example of lazy casting with a heavy fly! The dropped belly of the line will more than likely create a trailing loop.

An old photo from early days on the Jan du Toit. I’d like to say that is planned but it is actually a good example of lazy casting with a heavy fly! The dropped belly of the line will more than likely create a trailing loop.

The most obvious irritation and cause for difficulty when casting heavy flies is that fast casting that creates tight loops will result in the fly stopping abruptly before it begins its movement in the opposite direction – this creates a feeling of a bump or bounce that is particularly noticeable on the backcast. A little bit like an overwind on a baitcaster, for those who have played with such tackle.

This action of the fly ‘stopping short’ results in the equal and opposite reaction of the fly’s speed, although briefly, being faster than that of your rod tip and flyline. This results in a loss of tension in the fly line which results in a dreaded trailing loop (also known as a closed loop). And trailing loops cause nothing but agony: messy and off-target presentation, crossed lines, wind knots, hooks catching your rod (or a heavy fly knicking or hitting your blank causing a break) or even a new piece of feathered jewellery adorning your body somewhere.

A Trailing or closed loop created by the loss of tension in the fly line.

A Trailing or closed loop created by the loss of tension in the fly line. This is a clear diagram of what is happening in the photo above.

The arrows highlighting possible tangles and the position of a new piercing!

The arrows highlighting possible tangles and the position of a new piercing!

So, to cast those heavy flies, whether it be a tungsten beaded nymph on your #0 or an ugly, lead dumbell eyed Clouser in the brine, take note:

Firstly, SLOW DOWN YOUR CAST. This will automatically cause a WIDENING OF YOUR LOOP. We have had the fact that tight loops are good and wide are bad shoved down our throats for so long that many fly fishermen don’t realise the the useful application of them. When you are casting a heavy fly, a wider loop will cushion and smooth the flies direction change. This cushioning through motion gets rid of the bump that causes line slack and the trailing loop.

By widening your loop, the heavy fly is smoothly brought into the direction change and does not have time to form a trailing loop.

By widening your loop, the heavy fly is smoothly brought into the direction change and does not have time to form a trailing loop.

And great way to widen your loop without slowing down too much is to master the BELGIAN CAST, also known as the Oval Cast. This cast requires you to CHANGE THE PLAIN OF YOUR ROD TIP as you cast. Sidearm cast back and forward over the top without a pause between the two. It is explained very clearly in this video of Bruce Chard.

The last tip for heavy flies it to AVOID QUICK DIRECTION CHANGES OF THE CAST. This causes the strange curves and bends on the flyline because of good old physics: the heavier something is, the less it wants to change its direction when moving. (It has to do with Newton’s First Law of Motion). This obvious leads to messy and off-target presentations, – you know the list!

JUST A NOTE: Heavy flies are different to big flies.