What I learned about hafting glue(pitch glue) is that the charcoal and rabbit droppings have the same properties for the glue, they both add body to the mixture so use either one or the other. Both are not needed but it won't hurt anything to use both.
I don't have a recipe but I start with hard, brittle pitch, add enough bees wax(or other oil) to make the pitch less brittle and the finely ground charcoal or dried deer or rabbit manure to add body to the mixture. The fibrous dried deer or rabbit manure can also add some strength.
I melt the pitch and add and blend enough bees wax so the pitch is still hard but you can push a finger nail into it without it crumbling. You'll only know how much beeswax to add by letting that mixture cool first. Then I reheat and add enough charcoal to give it more body. I've also used fine saw dust for this. It will give you a different color than the charcoal or manures.
If you use hard but sticky pitch the resulting mixture will stay sticky after it cools and will stick to any and everything. The hard brittle pitch will cool hard but not sticky.
Be very careful heating the pitch. It is highly volatile and will combust if over heated. Best to do this outside and away from anything flammable.
