Hello Paul, I would have to say that you were just dealing with lot to lot variations in the same powder designations. Especially when a number of years pass between lots.
I would also have to say that Surplus powders are probably not as consistent lot to lot as regular "canister" type powder available to the public. I wouldn't even depend on consistancy between a surplus and commercial grade of the same powder designation.
I guess the soundest advice was always to reduce a load when changing any components and especially when using a different lot of the same powder. You never know.(only the toes,knows)
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