keep in mind:

1) NO factory uses canister-grade gunpowder, which is what is available to the reloader. So the powder can't be duplicated, only the results.
2) NO factory loads powder by weight(grains). They ALL load by volume, and contrary to most peoples ill-informed notion; volume devices are NOT a way to get a desired weight of powder.

Especially with Extruded powders, they are designed for a volume. They have a very tightly controlled relationship between B.D./B.R. So a Consistent volume will control the changing BR/BD, and a consistent volume will also keep the additional variation of shifting burning rates due to case volume, to a minimum.