I put the weight under the bobber to make the bobber easier to pull under the water by the fish, and it gives me a little bit more weight to cast with. Also, by putting it there, I end up with less tangles when I cast out and the maggot falls thru the water column more naturally than if drug down by a weight. Size 10 hook, one maggot on the hook, the bobber is made of stryofoam and is maybe 5/8" dia and 3/4" to 1" tall. The bobber either has a slit in the side or just a hole drilled thru the center. The line is held in place by jambing in a small piece of wood about the size of 1/3 of a round toothpick. I can cast that combo about 60 feet with the small split shot under the bobber, 40 feet without it.
I'll also use a Berkly Micro nymph on a 1/100 oz. lead jig head - no weight or bobber. Casting it with anything heavier than 4# test is futile, 2# is better.
