What is an avoirdupois ounce?
An avoirdupois ounce is the ordinary ounce of the imperial and US customary systems, as opposed to the troy ounce used for gold and silver.
It is equal to 1/16 of a pound or approximately 28.35 grams. The avoirdupois system is based on a pound of 16 ounces, with larger units such as tons and pounds used for heavier measurements.
What are grains?
Grains are a unit of measurement commonly used in the imperial system to measure the weight of small objects such as bullets, arrows, and jewelry.
One grain is equivalent to approximately 0.0648 grams or 0.0023 ounces and are still used in certain industries where precision is crucial, such as in the production of pharmaceuticals and supplements.