I know its probably been asked, but I'm looking to spool my Lew's MB w/Fluoro for jigs/plastics. I'll throw anywhere from 3/16 to 1/2 oz. Will backing or no backing help me cast farther? I'm not worried about cost effectiveness... Also, how much backing/mainline on a 120 yd spool?

I'll let the experts tell you if it makes a difference, but imo I don't think it would.  As long as you filled the spool to the right level, I don't think it matters much. 

 

For jigs and plastics, I'd put 50% backing on it.  If it was cranking I'd want 80 yards at the minimum of floro. 

I'll let the experts tell you if it makes a difference, but imo I don't think it would. As long as you filled the spool to the right level, I don't think it matters much.

For jigs and plastics, I'd put 50% backing on it. If it was cranking I'd want 80 yards at the minimum of floro.

I don't crank w/fluoro (personal preference thing) but I will be making long cast w/the jig.. Time will tell. I'll have to do some experimenting.

Backing is subjective, I typically put some regular mono on for a filler. I do it to cut down on cost. I have also spooled new reels without a filler. I havent noticed a difference in casting distance. I will say this, dont put too much backing on. A couple of times I have put on more than I thought, and ended up seeing the knot when I make a long cast. If you arent worried about the cost, I would say just spool it up without backing.

Backing is used to fill room on the spool so you don't waste good line. You aren't going to reach the second 1/2 of the spool on a cast. So you'd have approximately 60 yards of good line that never sees the water. Using backing allows you to spool 2 reels with good line. Using all fluoro or 1/2 and 1/2 won't matter for distance if you fill the spool up to a proper level. How much to use depends on the diameter of the backing and the diameter of top shot. I think most spools give you a rating for #12 mono. So use 50 yards of #12 mono and then spool up with top shot that's equal to #12. Adjust for larger diameter lines.

The only time backing is supposedly beneficial to casting is when using light weights, a braid backing is supposed to be lighter and helps your spool speed up faster. How effective this is in real life I do not know. Your jig will be no where near light and I would actually want as much weight on the spool as I could which would be all fluorocarbon.