Molly is correct in the King-deal. This is the standard of measurement in the IMPERIAL scale, however wheat is not used for proving scales today.
Goes on 437 1/2 grains(of wheat) to an ounce.
As well, 27 1/3 grains (of wheat) to a dram.
I have a number of 3 dram powder measures that I MADE to throw stricken WEIGHTS of powder at 82grains 2F GOEX, thus 3 x 27.3 = 81.9gr. - close enough to 82.0grains for me.
I take a brass tube of appropriate size, dump in a weighed measure of powder that has proven to work in a certain gun, then mark and cut the tube, so that it "THROWS" that WEIGHT of powder. I record and/or remember the stricken powder measure needed to throw the correct WEIGHT of powder for each gun.
3 Drams is my trail walk squib load for my 14 bore rifle and as well, my long barreled .50 also seems to like this load, although I have not 'worked' up an accuracy load for that rifle, yet - I must do that soon.
CTG cases picked up off the floor at the range can be used to make powder measures.
Photobucket is closed right now for maintenance - so cannot post a picture of a few powder measures I have made. The smaller the diameter of the powder chamber, the more accurately you can throw the charges. The larger the diameter of the measure the more variation per "throw" you will get. For example, a 3/8" diameter 'measure' will throw more accurate loads than will a 1/2" or 5/8" diameter measure.
Most adjustable measures are in the 3/8" to 7/16" sizes. These, with practice, can throw charges with less than 1 grains weight variation, throw to throw. The least accurate measures are those made from cow horns with grossly tapered cavities & may vary, depending on design & size, from 2 to 5gr. weight differences. While this may not be noticeable on a field or trail walk shoot, it can make a difference in precision accuracy contests like bench, plank or chunk shooting - where some contestants actually weigh out powder charges and have them per-measured, as in weighed and stored in small containers.
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