Blood Knot VS. Double Uni Knot Strength Contest (Mono-To-Mono)

We are back with another knot contest!

How will the blood knot stack up against the double uni knot?

This contest tests the strength of both knots with a mono-to-mono connection for a beefed-up tip on the end of your leader.

It will also apply for fluoro-to-mono connections.

Check out the results of the test here!!

Blood Knot VS. Double Uni Knot [VIDEO]

Sign up for FREE to receive the latest saltwater fishing videos, tutorials, product reviews, and fishing product discounts!

➡ Click here to join the Insider Club

Equipment Used:

The blood knot proved to be a strong knot as well as a more streamlined knot when compared to the size of the double uni knot.

The knots are tied with a 20-lb line and a 30-lb line.

For both knots, turn the 20-lb line five times and four times for the 30-lb line.

How To Tie The Blood Knot

The blood knot begins with the end of each line overlapping one another with the tag ends going in opposite directions.

Starting with the 30-lb line, go around the 20-lb line four times and then through the center hole near where the lines cross.

Hold onto where it comes through the center hole.

Then, with the 20-lb line, go around the 30-lb line five times and then go through the center hole that is created.

Finally, pull the lines together tight to form the blood knot.

How To Tie The Double Uni Knot

To begin with, the setup is the same as the blood knot.

With the 30-lb line first, create a loop with the line up against the main line and follow the tag end through the loop four times.

Then with the 20-lb line, do the same as with the 30-lb except loop it through five times now.

Pull each end to tighten.

Knot Strength Test Results

The test was conducted in six separate trials.

Half of the tests were done without saliva applied to the knot and the other half were wet with saliva before cinching it down.

For every trial, the line was soaked in water for 10 seconds beforehand.

After the six trials, the blood knot was 13% stronger than the double uni knot.

The beefed-up tip or “Dirty Deeks” leader is used to prevent abrasion on your leader in the case of catching snook or tarpon where their tough jaws can rub up against your leader and lead to break-offs.

That is how most line-breaks happen.

An added, heavy line connecting your lure to a lighter leader and then to your mainline creates a stronger connection to your lure while still having the thinner line in the water.

Another result of the test is that the blood knot performed better when cinched down with saliva as opposed to being dry.

The opposite applies to the double uni knot where the dry knot outperformed the wet knot.

If you choose to tie your beefed-up leader with the blood knot, be sure to apply saliva to it before cinching it down!

Have any more questions about either of the knots in this strength test?

Please ask me down in the comments!

And if you know someone who wants to learn more about fishing knot strength, please TAG or SHARE this with them!

P.S. Want access to our best fishing spots and tips, plus discounts to our online tackle store? Click here to join us in the Insider Club!

Related Articles:

Related categories:

Notify of

Inline Feedbacks
View all comments
9 months ago

It would be interesting doing this same shootout with dissimilar lines since we’re often told that the blood knot isn’t suitable for that application.

Luke Starnes
2 years ago

If the braid to mono test comes back as the same I will definitely be switching to the blood

Richard Thompson
2 years ago

I’ve been tying the surgeon knot for joining mono to mono, I would like to see a test on that knot. Keep up the great work

Jeff Tryon
2 years ago

Always great info!

Luke Simonds
2 years ago
Reply to  Jeff Tryon

Thanks Jeff!

Stephen Allen
2 years ago

Cool stuff, thanks for sharing. I would not have thought the results would end that way.

Luke Simonds
2 years ago
Reply to  Stephen Allen

My pleasure Stephen. Glad to see that you enjoyed this experiment.

Jay Earley
2 years ago

Can’t wait to see braid to mono test

Luke Simonds
2 years ago
Reply to  Jay Earley

Me too

Robert Glassen
2 years ago

If you get a wind knot tangle that you can’t get out and you have a lot of braid out, a blood knot makes a good emergency repair. Leave your line out and cut out the wind knot. Then tie the ends together with an 8 turn blood knot and trim the tag ends close. You have to use 8 turns and pull it up tight because braid is so slick. It’s a very small knot so your spinning reel will still work. It doesn’t make any difference with a casting reel. You can put new line on when you get home.

Luke Simonds
2 years ago
Reply to  Robert Glassen

Thanks for leaving the tip!

Rob S
2 years ago

Hi Luke, I understand you saying similar diameter of two lines. Do you have a feel for how much difference (e.g., 20/40; 20/50; 40/60, etc.)? Do you think this applies to very light or heavier line connections? I’m sure the knot ties with other diameters but not sure if knot strength is compromised. Thanks.

Luke Simonds
2 years ago
Reply to  Rob S

I haven’t done detailed testing on the blood knot with lines of very different diameters, but I know that it works because many people do use it… it’s just more difficult to tie since the lines aren’t behaving the same way while tying them.

As for the strength aspect, that shouldn’t be compromised due to line diameter changes because the mechanics of the knot still hold true… I just think that it’ll be smart to add more turns with the lighter/thinner line to help spread the tension load knowing that it’s the weaker of the two lines.

2 years ago

Hey Luke, thanks for the comparison. What knot would you suggest for heavy mono to thinner mono (e.g., 80lb to 20lb)? The uni knot for thicker mono (using 3-4 wraps only) seems to cause warping and almost immediately weakens the line, even when wetted thoroughly with running water. I can get a few instances without warping, but it’s not consistently repeatable. Lately I’ve done modified Albright but not too confident of that either and it’s not too easy to do in windy situations on the surf.

Last edited 2 years ago by Tuan Tran
Luke Simonds
2 years ago
Reply to  Tuan

I haven’t done a detailed test on 20 lb to 80 lb line, so I’m not sure for certain which knot would be best for that. My first thought is that the double uni would be a safe bet for being a good knot for that though (I’d just do 8 wraps with the 20 lb line to help spread the tension load.

Robert Glassen
2 years ago
Reply to  Luke Simonds

Try an Albright for that

Larry Mills
2 years ago

Can you use blood knot be used for mono to braid?
Also, are you still adding a free item to orders to offset shipping? My order didn’t have an additional item!

Luke Simonds
2 years ago
Reply to  Larry Mills

Yes, the blood knot can be used for mono to braid, but it’s more difficult to tie and not as strong as the FG knot so I don’t recommend it.

The free gifts on tackle orders was just fir October.


Do what the “SMART ANGLERS” are doing and join the Insider Club.

Here’s what you’ll receive today when you join:

Other Fishing Tips You May Like :

How To Set The Hook When Fishing With Big Paddletails

Want to catch more fish on artificial lures this fall? Big paddletails are your best option, but if you don't set the hook correctly, then...
See Full post

TFO Pro-S Series Spinning Rod Review

Now that the latest version is available, it's time for the TFO Pro-S Spinning Rod Review! This is the rod Luke used to catch his memorable...
See Full post
Would love your thoughts, please comment.x

Get Instant Access To “The Inshore Fishing Manifesto” PDF Now

You’ll automatically be emailed a private link to download your PDF, plus you’ll be added to the Salt Strong Newsletter.
(Please double-check your email below to ensure delivery.)