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Old January 26, 2014, 04:12 PM   #17
Unclenick
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Join Date: March 4, 2005
Location: Ohio
Posts: 21,721
Don P,

Your post indicated you matched what the OP threw in November. No problem there. The problem is that it doesn't match what the same disc threw for the OP in January, and that's when a scale setting error became one possible explanation and would need to be checked for.

A quick look at the Accurate site says No.2 has a nominal VMD of 0.102 cc/grain, but that its bulk density varies ±5.5%. That means the VMD might be as low as 0.09639 in one lot and as much as 0.10761 in another lot. That means a 0.32 cc disc could produce anything from just under 3.0 grains to just over 3.3 grains if those numbers are correct. Lee's table says the No.2 VMD is 0.08380, which is smaller than Accurate's tolerance at the low end. Since the powder is made to Accurate's specification, their numbers are going to be the more believable ones.

To me that discrepancy between Accurate's numbers and Lee's numbers suggests either that Lee measured just one lot and did it long enough ago that it's no longer a valid number for current production, or that Lee happened on a lot with a low end VMD for their testing, then reduced it an additional 15% to ensure handloaders without a scale erred on the safe side of actual charge weight. I don't know which.

With any of Western's powders (Accurate and Ramshot) just go to the product description page on their web site, click on a picture of the bottle with the powder number you are interested in and the VMD and bulk density and its tolerance are both available. Note that it give these numbers both for grams and for grains as the weight unit. I believe the grain unit numbers are on the lower row in all instances. Just read the units to check and realize that while they differ from Lee's numbers, it won't be by more than ten or twenty percent. If it's several times that, you've probably read off the wrong line.
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