Sinkers: sliding and fixed
A sinker looks like the simplest part of a rig: a lump of metal that pulls it down. In fact it decides not the depth but the rate of descent — and how much of a bite ever reaches the angler's hand.
One question splits every sinker
Does the line pass through the sinker? The answer sets the type and everything else. On a sliding weight the line runs straight through, so a fish that takes the bait pulls line while the weight stays put. On a fixed one the weight is anchored, and the fish comes up against it at once.
From there the behaviour on the bite diverges, and so does the rig, and even when to strike. Both are set out under sliding and fixed sinkers.
Shape decides whether you snag
A round, streamlined weight rolls along the bottom and passes over stone; a flat one holds in current but catches on everything. Shape is the choice between a weight that stays and a weight that travels.
On a stony bottom the one that snags less wins; in current, the one that does not get swept. Both are right, and both are a mistake if you confuse the waters.
Material sets the volume, not the weight
The weight is the number on the packet; what the material sets is the volume at that weight. A denser metal makes a smaller piece of the same mass, and a smaller piece snags less and alarms fish less.
That is the real difference between lead and what replaces it, covered separately.
The sinker is the sacrificial link
In a properly built rig the sinker breaks off first: it is attached so that a snag costs you the weight and not the whole rig. That is design, not carelessness.
The same logic as a hooklength thinner than the main line, described under leader material.
Sinker and float are one system
In float fishing the weight is not chosen freely: a float carries a stated capacity, and the shot is made up so that it sits at the right depth in the water. Too little and the float lies on its side; too much and it goes under.
It is the only place in a rig where another component sets the weight rather than the angler. In every other rig the choice is yours.
What it does not do
A sinker does not lengthen the cast by itself: past a certain point surplus weight starts damping the blank and distance falls. Nor does it make up for the wrong line — thinner line casts further at any weight, which is covered under how to choose line.
