Ammo makers do not use canister powders that are available to the public . Powders are formulated for a run of ammo and adjusted for that "Lot" to meet the requirements .
Pulling down a factory load , weighing the powder and identifying the powder by looking at it ... isn't the brighteset way to get safe load data.

If you don't believe me ...ask one of the ammo manufacturers what powder they use ... they can't tell you because it's not available to purchase . I.D.ing powder by looking at it is an iffy proposition at best and a dangerous proposition at worst .

Printed / published load data is still your best and safest bet .

My Dad would tell you " Boy ...Don't be acting the fool ! "
Gary

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