Gentlemen I have a number of powder flasks that I use with adjustable nozzles, all calibrated in Drams, or 27 1/3 grains when I have check weighed them on my scales. I definately would not be using the 60 grains as mentioned earlier.
This discussion of terms was a thread on another site, I am guessing that these chaps were a bit loose with the terms and it has caused some confusion ever since.
I have been using drams since the age of 12ys and had never heard of this discussion of drams vs Drachms till the last several years. The drachm was likely a liquid volume, and also liguid volumes could be given in grains, as I have read in at least one 19 century hunting book.
These chaps were not professional authors and my not have bothered to check certain terms were being used correctly.

Cheers

Gordon