I’ve always been on the understanding that a rig should be as strong as the leader but after getting a call last week from a fellow marlin fisho I had to test a few rigs. My fellow marlin fisho claimed to have lost his favourite lure to a XOX mack tuna in surprising circumstances. His claim was the rig he had, had been professionally prepared, it consisted of 100lb leader, 2 SL12s on 7x7 wire attached to the leader by a shackle. All in all it sounds like a standard rig for small blacks and sails. He had this xox mack tuna to the boat and by the leader when the rig broke at the leader side of the shackle crimp. I asked all the usual questions like, how many fish had he caught using that leader and were any of them wa hoo. No it was a replacement leader for an old one.

So I decided to replicate the rig and give it the Landcruiser test. With my rig attached to my car so that no part could possibly be compromised and the other to my 90kg certified scales I began reversing. After several attempts and preparing the rigs with different crimps, I can unhappily say, every rig broke at the crimp well under the breaking strain of the leader. I replicated the test once with just my own strength. After almost 5 minutes of digging my heals into a soggy lawn the line broke again at the crimp, again well under breaking strain.
All rigs broke at around 25 to 30kg

This is particularly interesting to me as I have had quite a lot of small to medium green, cranky black marlin on the leader and have never broken a leader anywhere on the rig. I put together another rig and put the amount of pressure on it I believe I put when leadering a fish, 15 to 20kg max, I would never have had to put more than that on any medium fish ever.

My overall conclusions are as follows.
Don’t over crimp as you crush the leader reducing the breaking strain. Best method is to feed the tag end through the correct sized crimp then with a lighter just heat the end up enough to create a bulge then pull it tight and give it a moderate to firm crimp.
With a fish on the leader don’t expect it to hold to the breaking strain, if you have 150lb leader the SL12s will pop at about 40kg.

I hope this helps at least some of you as much as it did me.
Total carnage included 5 bent SL12s
5mt 100lb Ande
14 crimps
And a pr of thongs.