long tails will bend out if OTG casting on shingle. I use long tails in sand and short tails on shingle for this reason.
ball sinker moulds can also be modified to make a fixed grip sinker, 4 – 5 ozs owrks well and will hold in ANY current.
You can get breakout moulds for around $65 to $70 have a nosey on trade me.
or get the genie mold at tackletactics or discount fishing supplies.