The rattles act as the lures heart in a way as it sends out pulses and attrates the fish in to have a look. Adding wieght to the lure might work but it could also mess a good lure up and they are designed to be that wieght to swim/track straigh and if you add to it , it might ruin the lure.

Give it ago mate but dont try it on a expensive one to start try a cheapy and see how it goes.

What are you targeting with the lures and what lures are you using?

bream/flathead, ive got alot of the RMG 52s so i thort it could be worth a shot, just looking for a bit more distance. currently using an okumo aquis30 reel on a 6'6" 2-4kg with 6lb line so i figure its not the gear, so if i can add some artificial skill it could improve things. Could go lighter line but ive had some back luck putting to much force into the cast and breaking off.

 RMGs cast fine i find on 10lb so they should be alright on 6? which line are you using mono or braid?

if you fill it up with liquid, it will ruin the action of the lure.

Could use a weight putty though, remove the middle treble and evenly add a putty weight or even crimp on a split shot. but even that may ruin the action of the lure

mono, been meaning to change to braid once i loose a bit more line of it. might try some split shot too, i dont see how liquid would ruin the action, might slow it down a bit, but then having it float up slower could mean the difference, might try filling it with a glue that could set or dip the bib in some lead set it and build up a layer or 2.

To add enough weight to get it to cast noticeably better you're going to have a lure that sinks pretty quick so thats something to keep in mind. Many lures already cast better, but for bream, its not necessarily about casting further, but casting smarter. If you cast a bit longer but theres no bream around or the action isnt right then increasing the weight wont help. I would think 52's, while still bream catchers might not be the lure size of choice for most bream fishos? Having braid on will allow you to twitch lures to a more effective retreive.

Strange you say a baseball bat cast. I tend to use a little light flick for bream lures (but have a nice flicky tip rod).

Have you tried out a few metal vibes by the way?

yeah i figure low and flat, works for me for light lures. i got a few of a FW member when he offloaded a heap of lures, they seem to work well for me, still get undersized bream on them alot. havent used vibes yet but the price is a bit daunting for a bit of metal plate. heard nothing but wonders about them thou. i come from a broomstick rod background and my 2-4kg rod to me is like a lackyband. its a solid tip thou so not sure if thats to good for lures. i dont think i need another rod but maybe refine some of my action and spend a bit more time getting it right then just wetting a line

The stuff aussie_breamer is talking about is called "sticky weight". Try Campbells Protackle, pretty sure its in stock there. Its on old product though so you might have to check the clearance section.

Why not swap to Braid and see how you go?

I say buy some braid, and if it stilll doesnt work, well then resort to this option :|

 i put a tiny little running ball sinker on the line to my lure once and caught a flattie =P think i was just lucky thought. wouldnt do it again..

ive tryed the running sinker, worked alright but its something else you gotta add etc etc, got some braid today, 5kg fireline exceed, smallest they had besides 2kg so thort id give it ago. thinner than the 6lb triline i had on so i hope to see a bit of an improvement. i have some 20lb braid i use for chasing bigger stuff but never delt with fine braid so it should be a bit of fun.

The ball bearings inside the lure are design'd to move to the tail on the cast. When you start to retrieve they move forward to the belly cavity and rattle, also creating the side to side movement. Just my opinion, but i think by adding a fluid or glue this would wreck the action of the lure.

But hey, give it a go and let me know how it works.

ill figure something out lol. just finished the deck out of another tinny i got so i might go fishing the lazyman way instead for a while

tonight i got a small blood blister drill, about .6 of a mm in diameter, i drilled two holes, one at the back and one at the front, took a mouth full of water and blew it into the top hole untill it started coming out the other one. dragged it threw a mates pool and the action seems to be more erattic and "alive", added im guessing about 2grams to the 52 and its noticeable in the cast, i dont know what the balls inside are made of but when suspended in water they seems to give the lure a bit more wobble..

as there are two holes the weight of water added can be eaisily changed and the holes are to small to let are water out due to the lack of surface tension im guessing when out of the water.

win i think, ill see what the bream decide this weekend.

seemed fine really, no difference in cast except distance was improved, ive super glued the holes on one now but wil be interesting to see how it does, it wont have as big of a ping in the rattle thou