Popularized by Southern California long-range tuna fishermen, the San Diego jam knot is extremely strong, retaining 95 percent of main-line strength when tied correctly. Used most often for securing heavy jigs, or "irons," directly to the main line, the knot can be tied quickly when you need to change lure weight or color in a hurry. As line diameter increases, the number of wraps should be decreased for maximum effectiveness. The San Diego jam can also be tied with braided line and is best snugged by hooking the jig to a stationary object and pulling the main line and tag end.
1. Pass the main line through the eye of the jig and double the tag end back over the main line.
2. Wrap the tag end around the doubled main line five times, moving towards the jig. Pass the tag end through the loop that has formed at the jig eye.
3. Pass the tag end through the loop on the main line that formed at the first wrap. Wet with saliva and pull the main line and tag end to snug it tight.