A frequently asked question by anglers both experienced and those new to the trolling scene is what copper line to use? 

There are a variety of options available, most often referred to light (32lb) and medium (45lb) and heavy (60lb) copper.

32lb copper is a great copper for the following scenarios.    Small Reels with low line capacities (45 Convector, Daiwa 47, etc), and shallow water setups (50, 100, 150 and 200 foot segments).

45lb is great option for both top water and mid range fishing, particularly if you have large reels with big line capacity.

45lb Copper and 32lb Copper have virtually the exact same dive curve despite the different in diameter and weight.   45lb copper runs on average only 3-5 feet deeper than 32lb copper...all the way out to 600 feet of copper being deployed.

32lb shines on small reels for obvious reasons, biggest is overall line capacity (or lack thereof) and small levelwinds.   Many forget that you have to get your copper knot or swivel through the levelwind on your reel, and most small reels will not allow for large copper knots to pass through.   32lb passes through with ease.

If you are only going to run short segments for top water fishing (less than 40 feet down) 32lb copper again wins hands down.   Leadcore lovers can complain all they want, but copper fishes completely different than leadcore.   Leadcore snakes and winds and cannot track straight into currents or penetrate any kind of significant temperature or current layer.   In fact, in recent depth testing, traditional leadcore could not attain depths any deeper than 37 feet down from 10 colors and beyond.   Once you master the current and trolling angle game, this will become more than obvious as to the importance of that factor.

Many fishermen have only small inline planer boards as well, and the 32lb copper barely pulls them back.   This is particularly nice when you want to have a nice wide spread rather than dragging heavier copper behind rather than outside of the boat.

60lb copper begins to take over around the 300 foot segments and beyond.   Denser and greater overall weight make this copper ultimately pull deeper, though depending on speed and current the difference is often negligible  between the lighter and heavier copper.

Heavier copper with a larger diameter and greater "drag" can create a rising effect in certain current situations and this is where we find 32lb and 45lb fishing very close to on another.   In most other situations, 60lb copper gets the job done and gets your gear down deep into the current and below the current where target species may be laying low.

It is recommended to pull larger inline planer boards with the 45lb and 60lb copper and longer copper segments, the shorter smaller boards have a tendency to pull back way too far and tangle with other gear.

45lb copper and 60lb copper also tends to fall quicker on the turn, so again if you frequently turn instead of straight line troll....watch your inside coppers on turns for snags on the bottom and crossovers with other gear.

Either way, all three catch fish.    It is not important to know exactly where these line types and segments are fishing, the only thing that matters is that they are catching fish and you can put them right back out there and not worry about an exact number on a line counter or lead length from weight or diving planer.