Casting swing – how far do you need to cast past your marker float?

Ever wondered just how far you need to cast past your marker float to ensure your lead lands on the marked spot? Maybe you haven’t considered it but if you let your lead go down through the water on a tight line it actually swings in an arc... so potentially ends up closer in than you think.

So how much allowance do you need to make?

We asked Jim Kelly & he came up with the excellent spreadsheet tool below. Here’s Jim’s comments;

For most situations swing is negligible, it is only a factor in very deep water close in. The assumption is that the lead falls on a tight line. In real life there is also a catapult effect backwards due to line stretch. Energy is stored in the line and when released the line shoots backwards. This can be easily observed if boating baits out, put the line under tension and release. I have no way of calculating this as it depends on:

• Type of line
• Velocity of lead on impact
• Mass of lead

Feathering the line or dropping the rod tip on impact with the water will reduce catapult effect. Catapult effect can be an advantage on very silty/weedy waters as it slows the lead down and hence it doesn't go as deep into the silt/weed.

Click here to open the casting swing calculator as a XL Spreadsheet file.