Because of the issues associated with what was then called "bulk powder", black powder is always measured volumetrically. In a perversion of logic, the common volumetric measures are marked in units of weight - grains. So whether measuring cannon powder, or pistol powder 30 grains of cannon powder and 30 grains of pistol powder will neither weigh 30 grains, and the resulting ballistic when burned behind any projectile in a barrel will vary hugely. Since any moron can make BP, it is always up to the moron to tune their load to a specific projectile and barrel to obtain a safe and accurate burn. Once the moron settles on a volumetric load of powder behind a projectile, said moron can quickly fill a volumetric scoop with an accurate load for a second chance at shooting the deer quickly bouncing off into the distance.
Thus the lesson for rocketeers - just get a volumetric amount of whatever powder you use that can quickly assure you propel your av-bay projectile out of the body tube barrel each and every time. If you have selected an amount where accuracy is critical lest the projectile fails to leave the barrel post-haste, or conversely wrecks the barrel, you have selected the wrong amount.
Centrifuge tubes are marked in grams, which is again a perversion of logic since generally liquids are measured in said tubes, and the fact of centrifuging might imply different items in the liquid have different densities. You would think they would be marked in cc's.
