Line Diameters and Breaking Strains
I grew up in the UK and have until recently always bought fishing lines according to their stated breaking strains.
So when I came to Israel and started to get interesting in fishing after a few years I naturally bought some mono to get me started in my newfound hobby. I always liked to fish light and so opted for some Berkley Trilene Maxx in the 4.7 Kg breaking strain. It felt nice and claimed to be thin for its breaking strain at 0.20mm. I like to test things so that's what I did and found out, unscientifically, that it actually broke at 3.7 Kg. So, okay that's 1Kg less than stated but I figured that a manufacturer should be more accurate with its labeling.
Fast forward a few years and I'm now using braid. PowerPro for the first few years and I always bought it on eBay from Shimreels - a very reputable dealer. PowerPro labels its products very nicely and the breaking strain is always more than stated so I felt good using their product.
But about a year and a half ago I registered with the World Sea Fishing Forum (an excellent source for info and help) and came across this 'sticky' thread:
Power Pro**CORRECT** breaking strains and diameters
After seeing the information there, and several people's recommendations in other related threads to ignore breaking strains and just look at the stated diameter, I got to thinking....
I had just bought some 16 lb YGK G-soul Upgrade PE X8 and was really impressed with how thin it was - I mean really thin.
G-soul Upgrade X8
G-soul Upgrade X8 Max 16 lb
That's when I noticed that the label on the actual spool states "Max 16 lb #0.8"
I wanted to know what this "Max 16 lb" meant - I mean what is "Max 16 lb"? I actually found the reasoning for the labeling on their parent company website:
Line Technology ⌈The Difference in Line Strength Is a Matter of Weight⌋ with a sub-heading: The Deceptiveness of Line Labellings
It is quite technical but what they are basically saying is that they label their product (G-soul Upgrade X8 in my case) with a maximum breaking strain (far above reality for some reason) to help anglers that want to compete in IGFA record claims; see here for an explanation of their world record application.
There is a general consensus that the Japanese line manufacturers' method of using the PE rating can easily be converted to a breaking strain in pounds simply by multiplying the PE number by 10. For example my G-soul Upgrade with a stated PE #0.8 is actually about 8 lb breaking strain, which just happens to be about the same as my non-scientific test results.
So try and forget breaking strain claims but try and get used to the stated diameter or the PE number (if you are thinking of buying Japanese lines).