To connect mono to braided lines, loop to loop connection is a sure thing if you use hollow braided lines.
When using solid braided lines, many knots like Albright, Alberto or Uni to Uni knot are used. However their break at around 60 percent of their line rating. I haven't had any problem using those knots for light lines, but I have had failure from all those knots when I used 80 lbs and heavier lines for tuna.
Many serious jig fishermen use Mid Knot or PR knot throughout the world. PR knot is a kind of extension of Mid Knot and it requires special bobbin (weighted and tensioned). the strength of the knots are close to 100 percent. I recommend every jig fisherman should learn how to make Mid Knot or PR knot. You can use regular bobbin modified to make PR knot, but Shout Bobbin is regarded as the best though it is expensive ($180).
Here is video to make PR Knot using Shout Bobbin.
I've put an inordinate amount of time into tying knots connecting braid to mono (cabin fever since is been pretty chilly for us coastal Texans). In any event I tied probably 100 uni to uni knots in the last couple weeks and tested their strength. Mind you I didn't put them on an Instrom tester or anything technical like that but since I was tying 50lb braid to 80 mono and fluoro I just pulled on it with gloved hands. Since its unlikely that I could pull 50+lbs of force on the line (braid breaks way above 'listed' strength anyway) If it broke then it was a bad knot.
4 turns in the mono or fluoro and 8 turns in the braid every time. Fluoro is much more difficult to get the wraps in the knot to seat evenly and because it is stiffer than the mono. Interestingly enough, when the braid broke, everytime it was right at the mono/fluor wraps when the knot was tied poorly. When everything was seated it wouldn't break no matter how hard I pulled.
What I found was that in every case that the knot broke, the braid wasn't pulling from the center of the fluoro wraps but under the top wrap. Taking care to look out for that I was able to get all the knots to hold under my best effort to break them.
Either way, everyone should try a bunch of different knots to connect the braid to mono and find one they like and can tie easily. Practice and practice.
I too have been playing with joining lighter line to heavier leader and have had the uni knot fail miserably. I know I can tie a uni knot in both lines separately with no problem and have it very strong, but uni to uni just seems to break too easily. The PR knot seems like a good solution.
Practice practice practice seems to be key. I'm not sure I'll swap to a PR knot but its worth looking at for sure.
Do most get away with a uni-uni knot? If so, whats your biggest diameter/weight difference you've used successfully.
I switched to the PR a few years ago and unless i'm using loop to loop or a splice this is what i use. very strong and really only takes a few minutes on a boat once you get the hang of it. never had one fail yet, knock on wood.
I've been using the PR knot for about 1 1/2 years know and I couldn't say enough good things about it. Once you practice it, it can be tied in about 2 minutes and it is exceptionally strong. It really isn't any harder to tie onto flouro than mono and it is very versatile with using different sizes of main and leader line. It is very castable through guides once tied properly, and you won't have problems bringing it through guides or rollers. It is an awesome knot!
Where did you guys get your bobbins? certainly not willing to pay 180 bucks for one at this point. yes yes, if it keeps the line together, I get that argument.....still, not willing to drop that much on a bobbin at this point.
btw - i had the same PR knot for 8 months in 2009 with the same leader on dozens of tuna, amberjack, etc. i finally have to cut it off for panama but only bc of the leader being too short . i dont recommend keeping one leader for that long....buuuut i was a bit lazy.
I have a 1800 Sargosa with a 8 ft custom casting rod. The sargosa is spooled with 65 suffix braid. I will be casting Shibukis and poppers in Venice. I know the PR knot and I have put a 125 pound shock leader on but it seems too thick and will not straighten out.
Would like to know what pound test yall recommend and what knot you suggest on the terminal end.