The volume for weight conversions are a bit wobbly at best. Densities of black vary across granulations, manufacturers, and lots within makers and granulations. So using a volume of black as a benchmark for Pryrodex is somewhat crude.

May I ask why you are using Pyrodex instead of black?

Were I doing it, I think I would start with something arbitrary but quite low and then build up until I reached a desired, reasonable velocity.

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BrentD, (Professor - just for Stan)
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