Use the lightest possible gear and also the most fresh bait. Maybe even go live... Also if you try burlying and using light gear with good fresh bait, i'm sure you'll be in for some success...
Hope it helps abit
Cheers
Anthony
i use, 30lb braid and a 60lb mono trace. Just one hook through a mullets mouth and the other hook in the tail. I have never caught a jack, but i got busted about 4 times in the tweed river with this rig. Hope the info helps.