Rapala Long Cast Minnows feature Rapala’s new weight transfer system. Essentially ball bearings move along a tube, inside the lure, to improve casting performance. I know what you mean. I agree with you that they still don’t cast anywhere near as far as a Tassie Devil or a Cobra.
The Rapala LC08 (freshwater) weighs a 1/4oz (7grams) and measures 3 1/8 inches (80mm) in length.
The Rapala LC10 (freshwater) weighs 3/8 of an ounce (10grams) and measures 4 inches (100mm) in length.
The Rapala LC12 (saltwater) weighs 11/16 oz (18.5grams) and measures 4 ¾ inches (120mm) in length. This is too big for a trout lure but I’m certain a trout would hit one trolled behind a boat.
An original size Tassie Devil weighs ½ oz (13.5grams) but is just 2 inches ( 52mm) long. When this lure is compared with the Rapala LC08 you can see the Tassie weighs twice as much but is only two thirds of its length. Plus it doesn’t have a second hook flailing about to reduce its aerodynamics still further. Hence the reason you are quite rightly able to cast the Tassie much further than the Rapala.
A Rapala CD7, which is used by many trout anglers for casting on spinning gear, weighs 1/4oz (7grams) and is 2 ¾ inches (70mm) in length. It is a “pig” of a thing to cast any distance even on 6 lb monofilament. I’d say 5 metres sounds about right! It is just too light and has an awful aerodynamic shape as well. However this particular lure sells well in the South Island as a spinner bait. The secret to fishing it on spinning gear is to know when and where to use it.
The Rapala CD7 works well when cast across a hole in the river that you suspect could be holding a trout. You can cast across the water, or walk quietly to the top of the hole and cast down stream letting the current carry it as far as possible. Allow the CD7 to sink, “counting down” from ten say, before you start a jerky retrieve. This will send all the right signals to any big predatory trout lurking in the depths of the hole.
Another situation where the CD7 comes into its own is where a stream or river flows into a lake. Get into position by wading out into the stream as far as is practicable. Then cast the CD7 downstream and allow slack line out so the lure is carried by the current over the drop-off. Again let it sink down before retrieving. Any big trout waiting below the drop-off for something tasty to come its way, having been carried by the river, will hit your Rapala big time! In this situation the Rapala CD7 “floats” into position until the slack line is taken up.
Otherwise you are correct in assuming that Rapala bibbed minnows are mostly used for trolling. It is rare to loose a lure when lake trolling so their cost is less of an issue. Mostly the lure is towed behind the boat with it well up off the bottom. Lure loses while trolling are more likely to be caused by angler carelessness such as accidentally wrapping line around the prop.
An additional casting weight in the form of a “D” lead would work. It would need to be at least 600mm up the line or it would completely deaden the Rapalas swimming action. The weight would need to be about an ounce to overcome the poor aerodynamics of the whole affair. Experience leads me to suspect there would be a couple of drawbacks with this arrangement. Firstly it would be difficult to cast without a sizeable percentage of tangles. Secondly the sudden force on the line would likely lead to bust-offs requiring the need to go to much heavier line; perhaps 15 or 20 lb mono!
I must admit that I would hesitate to cast a $20 Rapala in any situation where I might loose it. Generally speaking the Rapala offers the spin angler the best lure action through the water. It is the vibration from this wriggling action, even in still water, that causes a fish to strike. At the other end of the scale a ticer is the best for casting a long distance but unfortunately produces the least fish attracting action when retrieved particularly at slow speeds in still water. The Tassie Devil, or Cobra, is a good compromise between these extremes. I guess we are no closer to the fishing lure that is perfect in every situation