AdmiralDonSnider pipped me to the post on this one!
I've just discovered sinker moulds as well. I've always cast my own media, but as I made the mould by machining aluminium bar with a ball nosed end mill (which most people don't have the equipment for) I never bothered to write it up.
The sinker moulds come in several sizes, the only snag is that the there is a horizontal hole through the mould (to take the line I guess), but you could easyly block this at the ends with a bit of wood or fireclay - I'll probably screw a bit of metal bar in.
Experiments in progress, write-up on the greenman to follow soon...
PS here is the ebay shop I got mine from - I got the 44g size which come out about 3/4 inch
Sinker Moulds
Edited by phildunford, 17 January 2009 - 09:37 PM.