soft grains of black powder.

I had high hopes for my latest batch of powder.  It is only moderately
fast and very fragile.  The grains turn to powder between my fingers. 
Not good. I used willow charcoal.  My press dribbled some
alcohol/water as I pressed the cakes and they were pretty wet upon
removal. Does an over-dampened powder make for these soft grains?  Any
clues?  Can I salvage the powder by repressing?  Dan Cutter