This is widely used in pack baits by pay-lakers as it packs tight and breaks down quickly in water.
Millet Bait (makes about 0.5 gal).
3 cups hulled millet
1 cup wheat bran
1/2 cup soy meal
1 1/3 cup flour
4 oz of karo syrup
4 oz of liquid flavoring (maple syrup, any of the Superior Flavors, etc)
NOTE: If you use a "non syrup" (extract,koolaide) flavoring....you will have to add more Karo so that sufficient thick syrup is in the recipe for binding purposes.
Mix dry ingredients together
Mix liquid ingredients together and heat gently (do not boil)
Mix liquid into dry ingredients. Let set for a couple of hours.
This should pack into a rock-hard ball that will cast a mile without falling off and that will break down i the water within a few minutes.