dr
dram
Massexact by definition
The avoirdupois dram is one sixteenth of an ounce, exactly 1.7718451953125 grams. It survives in shotgun shell loadings, in some spice and flavouring trade, and in older US recipes.
Watch out: A shotgun shell marked "3 dram equivalent" does not contain three drams of anything. It means the load matches the recoil of three drams of black powder, and modern smokeless powder charges are a fraction of that mass.
| 1 dr | 0.0017718452 kg |
Where the unit came from
From the Greek drachma, a coin and a weight, by way of the Latin dragma. The apothecaries' system had a dram too, of 60 grains rather than 27.34, and the two coexisted for centuries in the same shops.
Solvers that use mass