Just a thought when someone says spider rigging I'm thinking your pushing jigs in front of the boat? Using heavy lead with a jig or minnow above the weight? That requires a very slow presentation of .01-.02 mph. If your long line trolling (pulling) different application all together. There the head weight, line size 6 lb., bait, or structure, is determined and speed and length of cast as well as size of line all play into the fray. There is a chart out there somewhere that is a starting place on running depths of head weights pulled at .08. This technique is what I love to do! I weigh each head I pour then test on the water finding a sandy flat using a short rod by the boat using gps speed watch as my jig bumps the bottom and that will give you an idea what depth your heads swim at .08. My 1/16 swim at 7.5-8' 1/24 swim at 4.5-5' 1/32 swim at2.5-3' deep. I use zig-zag slow turns as well on off trolling motor counting 5 sec. on 5 sec. off and let the fish tell me what they want! If your fishing brush piles like I am now I will time the boat as I go over pile depending on depth bump the trolling motor to get the jigs to be on the rise right when I guess they're over the pile. Well that's how I do it. ZigZag and off on really works!