Ask him for a WC-XXX number, or do not buy it. Unless he has loading data or reference to another powder that can be used for a guide.
For instance, WC-844 is very close to,,, or the same as Hodgdon H-335. Bulk WC-844 is NOT a canister grade powder, so it's burn rate is slightly different. Hence, you have to start VERY low and work up with each bottle of powder. Fortunately it usually comes in 8# bottles, and when I buy it, I get four bottles all from the same lot#.
The more people I meet, the more I love my dog
They're going to get their butts kicked over there this election. How come people can't spell and use words correctly?