Question about breaking strength and snares.

[justin_baker]

So lets say i had a piece of natural cordage, plant fibers, vines, roots, whatever, and i wanted to make a snare with it. Lets say the breaking strength is 5 pounds (it can hold up a 5 pound pack but not much more), will it be able to snare a 4 pound squirrel? Does the breaking strength of cordage directly relate to how heavy of an animal the cordage can handle?

[randyt]

I would think it would take more than five pound breaking strength to catch a four pound animal. think of a junk yard dog on a chain, he's going to give that chain a test and that's from a animal that is used to being restrained. that little squirrel has never been restrained, he's going to fight the snare jerking and pulling. this jerking and pulling will end up breaking the snare if the breaking strength is to low.I would think 15 pounds would be good for a squirrel. I have used thompson cable snares on coyote, bobcat and beaver after a catch those snares were trashed, the poundage on those snares are probably a couple hundred pounds. the above is just an opinion because I've not used a five pound snare before.

[Batch]

Too many factors come into play. What is the stretch of the cordage? What is the snare tied to, a stiff limb or a spring limb? How long is the snare? A longer snare and a stiff anchor will allow the animal to shock load the cordage more.
Also, the knots you tie will have a much lower breaking weight than the cordage itself.

[Pict]

There are ways to rig a snare so that the animal cannot apply all of his force to break it. Spring poles and drags are commonly used for this, the concept is similar to what a fishing pole does in spreading out the application of force over time to never exceed the breaking point of the line. Like catching a large fish, if you keep the tip of your rod up you won't lose him as easily as if you let him take a straight run at the line. You also set your drag to allow him to strip line rather than stretch it to the breaking point. You aren't there to control these factors with a snare set so you have to build them into the set itself.

I have lost squirrels with snare wire on pole sets because the animal stepped though the loop rather than getting caught around the head. This allowed them to struggle and wear out the wire until it broke. When the wire gets them around the neck they die before they can work the wire. Mac

[Rick]

I think it would depend on how you rig the snare. If you use a static ground snare then Randy is right. He's probably going to be fighting it. If you use a springed trigger snare then you'd have to account for the initial jerk but otherwise the animal is going to be dispatched pretty quickly.

[Rick]

We posted at the same time. Great minds and all.

[randyt]

I've had a "perfect" set snare catch a animal around the waist above the hind legs. the animals are alive and teed off it this point. in other words putting a strain on the snare. lol

[hunter63]

I would think using natural cordage would be able to be chewed loose, if a quick kill hasn't happened.

Most of my snares, I have made and used were thin wire, in a slip loop.
Effective and works even better with a fishing swivel tied in toward the tie off spot.
I have had the wire twisted and broke from fatigue.

[justin_baker]

Thanks for the info guys.
If i ever need to secure some food in an emergency situation, i will make sure to use string far stronger than what i need. Better yet, i would rely on a spring snare if using natural cordage. Less of a chance for disaster that way. I could see natural cordage breaking easily from sustained stress.

[crimescene450]

justin- have you made any good cordage? and if so what did you use?

[Coote]

A lot of what I would say has been said already.

Yep.... you have to consider the shock loading. Just like a bowstring might typically have a breaking strain maybe four or five times the pull weight of the bow, I'd say that a snare should have a breaking strain of of at least five times the weight of the animal. Preferably ten times or more.

It has been a long time since I studied physics, but I think that there is a formula more or less like this: Force = mass x acceleration. So if you have a four pound animal leaping about in a snare, you could say that it is accelerating as it springs thus exerting a greater force than its mass (weight) on the cord.

When a 80 kg man goes rock climbing, chances are the breaking strain of his climbing rope will be many, many times his own weight. If he falls any significant distance before the rope stops him, he will have created a big force. Also, a climbing rope is likely to be rather 'stretchy' so as to provide some deceleration (reduce shock).

Big fish are caught on a springy fishing rod that uses nylon line that might only have a breaking strain that is a fraction of the weight of the fish. But a skilled fisher doesn't allow the line to be 'shocked'.

If I had to use relatively weak cord for a snare, I might make a spring-up snare. Once the animal has a lot of its weight taken off the ground it cant get a good grip on the ground to jump and charge around.

Another thing I may do is to keep the snare cord as short as practical. This may restrict the 'run up' that the critter can do before it reaches the end of the rope. I also like to tether to a springy sapling if possible. This reduces shock.

By tethering a snare to a point that is higher than the animal, this may help to reduce the traction that the critter can get on the ground. As it reaches the end of the rope it tends to get lifted.

I have found that knots can be quite a problem when using natural fiber. Some knots seem to be stronger than others. I think knots which involve sudden changes of direction for the cord should be avoided if there is an alternative.

A deadfall trap can be made without using any cord. I still prefer snares for anything other than rodents though.

The NZ Maori people devised a cunning trap for rats which used fairly basic natural fiber. You will note in the diagram that this spring-up snare does not have the classical slip noose that is so often used. It has a simple 'stirrup' of cord which pulls the animal up against a hoop and holds it firmly not allowing it to turn and chew through the snare, and not allowing it to move around much.
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[your_comforting_company]

That's a neat rig. I can see a few mods I might make to it to make it adaptable to different animals or settings.
Thanks for posting. One can never know enough techniques!

[rwc1969]

erunkiswilderness has a youtube vid showing a trap simliar to that, but he doesn't go into tooo great of detail. I think he used a vine for his.