>If I make moonshine in a 5 gal. pot still from a grain mash such as corn
>.. Do I have to filter it through charcoal to make it safe to drink? Or
>will it be safe if I just throw away the first 4 or 5 ounces?
Always through away the first portion, no matter what else you do. This is
because it may contain some methanol, and other impurities, which can be a
little hazardous. Using carbon may remove a little of it, but its far
easier and safer just to toss it.
The question of using carbon is more to do with the flavour. You only use
carbon if you want to remove the flavour that is there - eg if trying to
make a vodka, or a neutral spirit to flavour using essences or fruit etc.
Given that you've used a grain mash, and a pot still, you're probably
after making a real bourbon/whiskey. In this case, you want to keep the
flavour, so don't use carbon.