Your Reel’s Retrieve Rating Changes Every Time You Drop a Jig

The number on the box is a full-spool number. After a deep drop, the reel in your hand may be a very different machine.

When you shop for a jigging reel, one number jumps out immediately: retrieve per crank. It may be shown as inches per turn (IPT), centimetres per crank, or as a gear ratio paired with a stated line-retrieve figure. It is easy to read that number as fixed: turn the handle once, retrieve that much line.

That is not what happens once you have sent a jig deep. As braid leaves the spool, the effective diameter of the remaining line pack shrinks. One spool revolution therefore pulls in less line, so one handle turn pulls in less line too. The reel has not changed internally; the geometry at the spool has.

This episode gives a practical way to think about the change without turning a fishing day into a laboratory exercise.

What the published retrieve rating really means

Published retrieve is normally measured with the spool filled to the maker’s reference level. That is useful for comparison, but it is a reference condition—not a promise at every depth.

Retrieve per crank = π × current line-pack diameter × spool rotations per handle turn

The spool rotations per handle turn are governed by the reel’s gearing. The changing variable is the current line-pack diameter: the outside diameter of the braid remaining on the spool. When that diameter shrinks, retrieve per crank shrinks in direct proportion.

For a fast on-the-water estimate:

Actual retrieve ≈ rated full-spool retrieve × (current line-pack diameter ÷ full line-pack diameter)

This is the useful rule: if the effective diameter is 15% smaller than full, retrieve per crank is roughly 15% lower.

The on-the-water method

You do not need the arbor diameter, braid thickness and a full wrap count to make a useful estimate. You only need a quick way to compare the full line-pack diameter with the remaining line-pack diameter.

1. Start with the published retrieve at full spool. Treat it as your full-pack baseline.
2. Estimate the full outside diameter of the line pack. This is the spool diameter with line filled to the reference level.
3. Estimate how far the braid has dropped below that level. Measure it as a radial drop on one side, then subtract twice that amount from the full diameter.
4. Scale the published retrieve by the diameter ratio.

For example, if the full line-pack diameter is 60 mm and the braid is sitting about 5 mm lower on each side, the current diameter is approximately 50 mm:

Current diameter = 60 − (2 × 5) = 50 mm

The diameter ratio is 50 ÷ 60 = 0.833. A reel that was rated at 52 IPT at full spool is now retrieving about 43 IPT.

Worked example: a “52 IPT” reel that is now closer to 43

Assume a reel is rated at 52 IPT (about 132 cm) with a full line-pack diameter of 60 mm.

The practical point is not whether the answer is 43.3 or 44. The practical point is that the reel is no longer behaving like a 52-IPT reel once a meaningful amount of braid is off the spool.

A second example you can do in your head

Suppose a reel is rated at 117 cm per crank with a 60 mm full line-pack diameter. Round the baseline to 120 cm and use an easy ratio:

120 cm ÷ 60 mm = 2 cm retrieved per millimetre of line-pack diameter

If the braid is 10 mm lower on each side, the diameter is about 40 mm. At 2 cm per millimetre, retrieve is about 80 cm per crank. Using the exact published number gives roughly 78 cm, or about 31 IPT.

That kind of mental conversion is enough to explain why cadence feels different at the bottom than it did at the start of the day.

Why this matters when you are jigging

Cadence changes. If you normally lift the rod and add one handle turn to create a certain jig action, a smaller line pack reduces the horizontal and vertical recovery produced by that handle turn. Your timing may need to speed up to maintain the same jig speed.

Recovery windows change. A fish that eats near the bottom may be more difficult to keep clear of structure when the reel is retrieving less line per crank than the printed number suggests.

Depth changes the feel of a “high-speed” reel. A reel that feels very quick at shallow depth can become moderate once the line pack is reduced. This is one reason a high listed IPT should not be treated as the whole story for deep jigging.

Make a one-line reel note before the trip

A simple way to use this without measuring every time is to make a small note for each reel:

Retrieve constant K = rated retrieve ÷ full line-pack diameter

For the 52-IPT reel with a 2.36-inch full diameter:

K ≈ 52 ÷ 2.36 = 22.0

Then estimate actual retrieve by multiplying K by the current line-pack diameter. If the line level looks roughly 0.2 inches low per side, current diameter is about 1.96 inches and retrieve is about 43 IPT. If it is 0.4 inches low per side, current diameter is about 1.56 inches and retrieve is about 35 IPT.

Limits of the estimate

This is an estimate, not a factory calibration. Braid packs imperfectly, line diameters differ, spools taper, and a reel may not be filled to the maker’s reference level. But the proportional relationship remains strong enough to be useful: less effective diameter means less line per spool revolution, which means less line per handle turn.

The method is especially valuable when comparing retrieve feel between shallow and deep work, or when deciding whether a reel’s rated speed is appropriate for the water column you actually fish.

Source and editorial note

This episode adapts a common Japanese jigging calculation for estimating actual retrieve from current line-pack diameter. Editorial source: Densetsu Kaicho / Jigging Soul.

Episode audio source