It’s ironic that lead-core line has become all the rage for big-lake trout and salmon fishing. The line has been around since before the invention of downriggers. But anglers are rediscovering how simple, yet effective, lead-core line can be.
It imparts an action to trailing lures that can't be duplicated with any other method, and excels when fish are shying away from more traditional techniques and presentations. Alternatives, like non lead-weighted line and braided copper line, perform like traditional lead-core line and are viable options. Though alternative lines cost more than double the price. The non-lead line has a sink rate similar to lead core. Copper line sinks much faster and deeper than lead-core line. Because of the sink rates of braided copper, less line is needed to obtain the same depth as when using more lead-core line. Trade-offs with copper line are its cost, larger diameter and its propensity to kink.
Lead-core trolling line is made with a nylon-braided sheath and an extruded, lead center core. The outer sheath of nylon changes color every 10 yards, and is used as a gauge to keep track of exactly how much line you have out. Anglers refer to the colors when describing how much lead-core line they have out. Basically, the more line you let out, the deeper the trailing lure will go. Lead-core line is available in 100-yard and 200-yard spools. In trolling jargon, a full core is 10 colors of lead core line or a full, 100-yard spool.
Cabela's lead-core line has some added features. The line is also lubricated, which makes it slip through guides easier, and the finish is heat-set for colorfastness.
Lead core line is available in different pound-test lines. The breaking strength refers to the nylon sheath and not the weight of the line. 27-pound lead core is stronger than 18-pound lead core, but it is not heavier. During tests I've conducted I found that a 100-yard spool of 27-, 36- and 45-pound test lead core line weighed nearly the same with only .06 pounds difference in weight between the spools.
10 colors of lead-core line being pulled at approximately 2.5 mph will sink to a depth of about 50 feet. How do I know that? Because I have had 10 colors of lead core out and gotten snagged on bottom in 50 feet of water. How deep the line actually sinks is kind of irrelevant. If you have five colors of lead core line out and 75 feet of backing and you're catching fish, all you need to know is how to duplicate that exact presentation. The colors on the lead-core line will allow you to do that. Realistically, you can figure that for every color of lead core (10 yards) you put in the water it will sink five feet if you are trolling at an average speed of 2.0 to 2.5 mph.
So why use different pound-test lines of lead-core line? For the same reason you use different pound tests of monofilament line for different species of fish. The most commonly used pound tests of lead core for big-lake trout and salmon applications are 27- and 36-pound-test line. Walleyes anglers prefer 15- or 18-pound test. You can fit the smaller diameter line on smaller, walleye-size reels. With species like walleyes, you also don't have to worry as much about line breakage. The more lead-core line you put on a reel, the bigger the reel you're going to need.
Fishing long lengths of lead core line requires some specialized tackle. A full spool of 27-pound test lead-core line will not fit on a traditional downrigger reel and allow much room for backing. A reel that has the capacity to hold 325 yards of line is perfect for using three-, five-, or seven-colors of lead-core line, but the reel is too small for a full core. If you're going to fish with 10 colors of lead-core line or more you need a reel with a line capacity of between 350 and 475 yards.
Rods for lead-core line are a matter of personal preference. There is no perfect lead-core rod, but longer, diver-type rods provide an advantage. A perfect lead-core rod is a 9 to 9-1/2-foot diver rod. With the longer rod you can keep more line out of the water, you can lift boards at critical moments and you have more leverage on the fish. With each lift you take up more line with the longer rod. To land fish consistently when using lead-core line you need to be aggressive and concentrate on keeping the line tight and remain in constant contact with the fish. Dragging the weight of the heavy line, it's very easy for the fish to create slack and shake free of the lure when using lead-core line.
Backing is important when fishing lead-core line. To get the full sinking effect of the line you need to have the entire lead core in the water, regardless of how much you're using. Also, if you're running the lead-core line off of in-line boards, you don't want to attach the board directly to the lead-core line. It will weaken it at that point, causing the sheath to fray and eventually break.
Super-lines are ideal for lead-core backing because they're strong, abrasion-resistant and have a very small diameter. Favorite super-lines are the 10/30-pound test line in the flame green color. Super-lines are tough, doesn't abrade when attached to planer boards and the high-vis green color makes it easy to see where it's entering the water.
Lead-core leaders can be standard monofilament or fluorocarbon. It's a matter of personal preference. Leader length can vary. I would normally start out with a 50- to 75-foot leader of 20-pound test and cut it back each day checking for frays and abrasion. Once the leader gets down to 15 or 20 feet, replace it.
Connecting lead-core line to backing and to leaders can be a little tricky. There are several knots you can use. My favorite is a Nail Knot like the one used to connect fly lines to leaders.
Sometimes the knot will slip off the end of the lead core. In that case, remove about two inches of the lead from the lead-core line near the end and tie an overhand knot in it. The nail knot will then jam down against the overhand knot when you tie the nail knot and keep it from sliding off. With a little patience and practice you'll get the hang of tying the nail knot. It makes for a very strong, small knot that travels easily though the guides.
How do you know how much backing to put on the reel with lead–core line? A simple solution if filling multiple reels is to put the lead-core line on the reel first and then fill the reel with backing. You'll have the exact amount of line on the reel– but in reverse. Now connect the backing to another reel and reel the line on to the new reel, but stop when you have just the backing on the reel and make note of how much line is on the spool by measuring the remaining space on the spool. That way, when you fill subsequent reels, as long as they're the same model, you'll know exactly how much backing to put on the reel.
Lead-core line can be run directly off the back of the boat or off planer or in-line boards. The advantage of running lead core off boards is that you can fish multiple lines, cover more water and keep tangles to a minimum. By fishing with various lengths of lead-core line you can cover different depths. Shorter lengths are run on the outside boards and longer lengths on the inside. The larger planers and in-line boards are ideal for lead-core line. They will pull long lengths of lead core far out to the side of the boat and the release system on the boards makes it quick and easy to get the line free when a fish is tugging on the other end.
Most captains will admit that catching even hard-fighting fish like salmon on lead-core line is not the most fun way of putting fish in the box. But the fact is, lead-core line catches fish when nothing else will.