I use a black powder dipper from the 1800's that measures black powder in "drams", a measure of BP by volume, and was typically used for shotgun shell loads
Oh dear, here we go with the silly Grains/Volume stuff again.
Excuse me, but a dram is a measure of WEIGHT, not volume. Look it up. A dram is 1/16 of an ounce. Sixteen ounces to a pound and sixteen drams to an ounce. Period. If you do the math, with 7000 grains to a pound, a dram equals 27.34375 grains. That's weight, because a grain is a measurement of weight, not volume.
The Dram Equivalency that we sometimes see on a box of shotgun shells (don't see it much anymore) refers to the velocity a given modern Smokeless shotshell achieves. A 2 3/4 Dram Equivalent Smokeless load will achieve the same velocity that 2 3/4 drams (about 75 grains) of Black Powder would have achieved. For instance, for years, a standard 2 3/4" 2 3/4 Dram Equivalent target load of 1 1/8 ounces of shot would have a muzzle velocity of 1145 fps.
By the way, think about that 75 grains for a moment. That's more powder than in a 45-70 cartridge.
The whole concept of Grains/Volume came about when the Black Powder substitutes such as Pyrodex first appeard. Pyrodex weighs considerably less than real Black Powder does, but it has been formulated to have pretty much the same energy as a similar
Volume of real Black Powder. So the easiest way to portion out Pyrodex was to use a Black Powder volume measure, like this:
You set the measure for the appropriate charge of Black Power, and you would get an appropriate amount of Pyrodex that would perform like the same charge of Black Powder.
Sure, we measure Black Powder by volume. When I load cartridges with Black Powder, I use a BP powder measure that portions out the powder by volume. Guess what? Smokeless Powder is measured by volume too. But the difference is, you set your volumetric Smokeless powder measure to portion out the correct charge by WEIGHING the charges, until the setting is right where you want it. Then you go to town and load all your cartridges using your powder measure that portions out the charges by volume.
When I load metallic cartridges with Black Powder, I choose a powder charge that will be compressed about 1/16" - 1/8" when the bullet is seated. But I do record the actual weight of the powder for reference purposes.
Yes, different brands of Black Powder do weight different amounts. I keep a chart in my reloading notebook of just how much my most common charges of Black Powder weigh by brand. I keep this chart just as a reference, nothing else. By the way, this data can change, because Black Powder can weigh different amounts, even the same granulation from the same manufacturer, from lot to lot. That is why most BPCR competitors weigh their charges, they do not use volume. And they will requalify their charges when changing to a different lot of powder.
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Back to shotshell reloading. Do yourself a favor and buy the Lee dipper set. Much cheaper than using antique dippers. Notice too, that the Lee dippers are calibrated in an actual volume unit Cubic Centimeters. That is the way I refer to all of my Black Powder charges. By how many CCs of powder they contain.
http://leeprecision.com/search.php?mode=search&page=1
You can also by an inexpensive adjustable shot dipper from Lee, but I simply use the 1 1/8 ounce charge bar on my MEC Jr.
http://leeprecision.com/adjustable-shot-dipper.html
If you want to know how much so many CCs of powder weigh, dip it out and weigh it. What could be simpler?
Sorry, I don't load brass shot shells. I load hundreds of shells every year and I simply use once fired 12 gauge Remington STS or Winchester AA hulls. I load them on a simple MEC Jr press one at a time. I use Circle Fly separate Fiber Cushion Wads, Over Powder Cards, and Over Shot Cards. Yes, modern plastic wads do perform better in modern shotgun forcing cones, but I like doing it the old fashioned way. Besides, my loads only need to knock down a target 20 feet or so away. They don't have to pattern well enough to knock down a clay bird on the Trap field.
A word about Square Loads. Yes, the old standard was equal volume of shot and powder. If you put more powder in compared to the volume of shot, you can blow your patterns. On the other hand, if you put in
less powder by volume than shot, you will not affect the pattern. My own loads have a bit less powder than shot, by volume. Simply because I am lazy and the largest dipper in the Lee set does not throw as much powder by volume as the volume of 1 1/8 ounces of shot.
