Gaillo's post on tiny weight variations evoked this question in my mind. Do commercial ammo manufacturers measure their powder by volume or by weight? I just assumed it was by volume, but I don't know that for sure. Does anyone know? And does anyone know what most of them would consider acceptable variations in powder charges? Just curious.

Most assuredly, volume.

And considerably less accurately than most handloaders who meter by volume. A one percent variation with stick powders (half a grain in a 50 grain charge) would be well within a factory's tolerance. That compares to most handloaders who would reject loads that were more than a tenth of a grain plus or minus.

However, the practical variation will be much closer when using ball-type powders, just as it is with most handloaders.

Working in the production industy myself and being around alot of automated assembly machines I would bet my bottom dollor it is volume.

Red, did you ever hear of a charge plate? Volume is the only feasible way for mass production.

Volume.

"Charge plate", ain't that that thing they send my wife a new one of right before every Christmas and she has wore out by New Years?
You know, with the big, tall, industrial-strength numbers on it.

quote:

Originally posted by Red C.:
Gaillo's post on tiny weight variations evoked this question in my mind. Do commercial ammo manufacturers measure their powder by volume or by weight? I just assumed it was by volume, but I don't know that for sure. Does anyone know? And does anyone know what most of them would consider acceptable variations in powder charges? Just curious.

They measure by volume. In the factory ammo from which I have pulled bullets and weighed the charges, the variation has ranged from as much as 1-2 grains to as little as 0.2 of a grain in some lots of .30/'06 stuff.