Same kind of thing here ... use lots of 3031 and 4064 and when i get down to low quantities of either falling short of a precision loading job at hand, place odd quantifies off to the side.
Then mix em all up, shake well and use it for plinking rounds at an @ 15% reduced load based of both load weight averages of each powder. Burns up the odd powders and never had issue ... Tho being smart about what ratios are in the blend.
Bad juju if you listen too the manufactures ... but in application what some of us long time reloaders do stretching dollars with calculated risk
Older and slower ... but Well Armed
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