I've commented on this before and thought I would expand on a modification I had made.
I carry my premeasured muzzleloader vial charges in a large rifle shell holder that slips on the buttstock of my rifle. I carry 3 power charges and 3 bullets stacked in a longer vial and the 5th vial is filled with primers.
What is different with this set up is I modified my standard vials to load duplex loads with the addition of a smaller vial that is cut and attached to the opposite end and it will accommodate my booster and the primary charge goes into the standard vial.
I trimmed both vials and then drill the base of the vial and heated the plastic and screwed the threaded portion of the small vial into the softened plastic and the cap secures it in place.
Pics will explain the procedure .
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