Unless the top hook eye is swept / angled  back a lot, there will be friction with the leader up against the steel of the hook eye, causing failure. especially if it's a cheap hook with a rough surface.

Another reason is that you're using a weak version of the snell or not enough wraps, or both. 

Hold the hook in your left hand with the eye side facing right. Thread the line through. Now grab the line to the right of the eye and start wrapping DOWN the shank towards the bend. Then feed the same line upwards back through the eye. This is the proper knotless snell. Tighten the tag end and the main together. Less wraps needed for thicker line. 10 wraps for 50lb mono. 


I can see your top hook in the photo. It's improperly  formed and tightened. Must tighten both ends of the line together. 

The bottom hook doesn't need to be a snell, use a uni or palomar or trilene. It's easier to thread the hook through the bait when the bottom hook isn't a snell. 

The reason for the top hook is to hold the bait in place and look natural.

The ONLY place a line will break is at the weakest point...Every knot, and I do mean EVERY knot is a weak point. Teeth or any other sharp thing is not a line break, it is a cut.

Look at the line after a break off. If the line is fairly straight and normal, then it was cut. If there is a slight curl of the end of the line it was knot failure. You might see (if you know what to look for) a slight flattening of the line near the break point, which indicates line burn caused by - knot failure.

The trilene as suggested by TJFT is the best. It is the only knot I use (for almost all applications). The trilene gives about 95% breaking strain. Some people claim it can get close to 100% which is BS. You might get above 95% if you really know what you are doing, take your time and be careful. But 95% is good enough for even the toughest of fish.

Because the top hook is only a bait holder and not a fish hooker, it just needs to stay above the bottom hook. A simple rubber (silicon) float stopper will do the trick. Or even some bait thread or even a rubber band.

Putting 2 knots whether snells or other, in a line without a solid break is bad. What I mean by a solid break, is like a swivel or ring etc. So that the line is not continuous.

If your knot on the top hook is not perfect you could easy be looking at 30% or 25% breaking strain on the bottom hook. Line burn is the biggest issue. No matter what knot you use, the friction of making the knot heats the line slightly which reduces it's breaking strain. Lick the knot...saliva is good for knots !! Never, and I do mean NEVER pull a knot tight...Always lick and slide.

As TJFT also mentions, angle is a big factor. With 2 knots in line without a break like a swivel or ring, there will always be an angle which will cause friction which will cause heat which will cause line burn. Sounds silly, but think about it. Say 0.8mm line. It would only take a split second of friction to cause line burn. But if that line was 8 meters dia it would take years in a blast furnace just to get the thing warm !!

There are also specially designed "keeper" hooks. They are not tied on at all. The eye is angled so that it causes an "S" in the line. So it stays in place to hold the bait, but is free to move when a fish is on. 

Fantastic info, thank you.
Have started to digest it. Lots to go through and test.
Started with a simple evaluation of my go-to terminal snell knot I use when tying a single hook compared to the advised snell, which I've steered clear of because of fears it'll come undone if ever unloaded. Even though my usual snell has never failed me, the true snell advised showed a minimum 50% increase in break strength. I say minimum because it actually didn't break but the hook straightened out instead.
I'm a bit shocked and will do some more testing. Early days yet but stoked to be learning.
Thanks again.

*edit* regarding the knotless keeper hooks, I've just done a quick google and couldn't find them. Can you please advise more info or a link please? Sounds very interesting. Might also help to reposition that keeper based on the size of the livie.

I can't find a pic of the hook I am thinking of. But this is similar to what I remember. But it is a long time and maybe what I remember was just an offset worm hook.

The idea is that the eye is offset so when the hook is lined up with the bottom hook it slightly grips the line.

There is no real reason why the top hook needs to be tied at all. It might be useful if the bait is very soft or worm like and you want to keep it stretched out. Otherwise, there is no real reason.

But if you do use a completely free running hook, it would be a good idea to have a small plastic bead between the 2 hooks.

How about using Kevlar cord for tying your two-hook rig? Then tie a swivel to the end and attach your leader to that.
I found Kevlar to be super strong and it holds up really well against abrasion from those sandpaper teeth.
I use it for all my jigs, stinger hooks and bridle rigs.

Thanks all. Lots to go through. Wrote a big reply but just lost it when I clicked off the page to look at something.

Still testing the end circle hook connection. Not much between the top four so far of true snell, palomar, trilene, springer. But much more to consider about that connection than just strength. How does the hook roll and set, how easy to tie when wet and I'm bouncing around in the kayak like a fly in a bottle, can I use the same knot for both 50 and 200lb mono, how does the livie swim, etc.

No need to put the line through the eye of the top hook. Looked at a keeper hook nail knotted to the leader separately so it could slide up and down and while it would mean no extra stress on the leader because the leader itself isn't knotted there, on any given day my livebaits could range from a little 6" nibble to a big and strong 4lb feast, depending on what bait and predators I can find that day. Trying to find something I can slide to adjust the length but then still hold strong without sliding, during what might be many hours of slow trolling, is quite a conundrum.

Started testing an all-braid rig (right to the hook, no 'leader') this summer but couldn't find enough fish to keep testing. Have found hollow core braid abrasion resistant enough for me but need to work out if it puts off kingfish / amberjacks in a slow trolled livebait context. Lord knows they are going to see it easy enough but does it really matter as much as the marketeers at the leader companies what us to believe? Will keep testing it next summer if the fish ever turn up and weather ever settles (has been the worst first 1/3 of a year for fishing I can recall up here).

I'm going back to the shed for more testing. :-)

*edit*
The springer knot is coming up roses, true snell second, in both strength and, surprisingly to me, roll/set of the circle hook. These two are also the easiest to tie in both 50 and 200lb. Can't retie onto existing leader using the true snell though unless also retying the FG knot at the other end of the leader.

So, looks like Springer is my new favourite knot. Colour me surprised but thankful for the learning. I will however 'road-test' the true snell on a one-hook rig and see if it comes loose and if so, if a small silicon bead will help keep it there. It may be there's not much risk of it coming loose in the real world but I want to find out one way or the other.

Trilene wasn't as easy to tie, doesn't offer any strength benefit (at least the way I tied them) over the springer and I'm not comfortable with the way it cinches down - seems like too much risk of degrading the line. But thanks for the suggestion it'saboat. Someone else more coordinated than I might find it the best.

Palomar was surprisingly strong but i get the impression I'd struggle on the water to tie it without crossing the lines and weakening it. It also didn't roll and set a circle anywhere near as well as the springer or snell.

Onto that keeper hook now. Trying to find the holy grail of making it adjustable without slipping on a bigger livebait, and not weakening the leader much if at all. I did try the nail-knotted sliding keeper a while back but never used the tube so will try it to see if it grips better. Although it's not as easily hidden in the livies mouths with the tube on. But then it would stop some chafing of the leader.

Hmmm, on the matter of heat shrink chafe tube, I wonder if some of that over a true snell would eliminate any risk of it loosening off. Obviously not something I can do when retying on the water but worth a crack on land just to learn.

*edit 2*

If the leader is held tight so it's slightly thinner than normal, and the keeper hook is tied around it via it's own, independent snell or nail knot or the like, then when the tension is taken off the leader then that keeper is on pretty snug. Probably tight enough that small and medium sized livebaits won't be able to slide the keep hook down the leader, but it can still be positioned along the leader by hand but it takes some force.

Unless there's another way, I think it's worth trialling it next time out.

Perhaps these sort of float stop beads he shows towards end of video, to position the keeper hook anywhere along the leader? I wonder if I can thread the end hook through the mouth of the livie and out a gill plate without doing any damage. This way the stops and almost all of the keeper hook are hidden down the livies mouth, but how long before it becomes a deadie with that arrangement.
https://m.youtube.com/watch?v=IeM-wvLI4Mo