yes JDB DNA follows USA type specs where 30lb can be easily 50lb ABS. like my Berkley X9 40lb from USA is actually 59lbABS. but if it is real 30lb Japanese spec PE 1.5 (approx 35lb ABS) it would snap casting a 5oz leader...I happily cast a 5oz no leader on my 14 6ft on 30lb JDB DNA, stuff is super strong but one man's cast is another man's whip, we all do it differently
Yes 40lb JDB breaks around 50 plus to 60 lbs so it would work with 4 to 5 oz sinkers no problem. it is USA over (or under depending how you look at it) specced.Out of interest I have been using my 15ft setup with 40lb JDB without a braid leader for the last couple months. I have been using 4-5oz sinkers and small baits, i.e. worms, prawn, mussels etc. and not clipping the bait. Only have a 0.70mm mono leader of ±2m which is just slightly shorter than my drop when casting.
My observations are:
1. I haven't cast off a sinker yet, also haven't broken off, mostly fishing this setup of the beach with maybe some scattered rocks.
2. I get about the same distance as with casting a leader but I'm focusing on casting smoother with a long drop as opposed to forcing the cast. The smoother action helps keep the bait positioned without adding to much latex or loosing half my prawns in the air.
3. The lack of braid leader seems to reduce the drag on the sinker and bait when in the water. I have got away with fishing cone sinkers instead of grabs on a few occasions, not really a scientific thing but I'm confident that you hook more fish using cones/pyramids than using grabs.. that's a story for another thread. Also not sure how much 3-4m of braid leader would ad to the drag, but it does seem to make a difference.
I'll see how it goes a bit later in the season when the clipped baits and lives come out.