Thank you Rick,
I don't think there is more than one powder horn maker enjoying the assembling of dual sets for wedding gifts

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... As to say there must be a reason for this 'bivalent' device to have been made. Let me have it back and check thoroughly whether there are any differentiation marks and if the two horns communicate with each other.
I am not a shooter, but i think of different gun powders for different types of load; implausible ?

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