Bass Pro Shops offers an oval splitshot called Clamshot. I use a variety of sizes on a variety of jighooks to obtain minnow shaped jigheads. I simply crimp them onto the bend of the jighook and mash them down somewhat flat. I then use powder paint which seals them shut. When crimping, I start with the pliars underneath and hold in the hook as I crimp to position the shot on the hook. I then place the pliars over the top of the hook and shot when crimping flat....this presses the two halves together solidly due to the angle of the pliar jaws in crimping. Once in a great while, the jighead pops off when heating for the powder paint, but most stay on. Once on and painted, I've never flung one off. Fresh out of the package, the clamshot look like little footballs split open lengthwise. They make excellent jigs.