Jon,
I loaded 125 rounds with 1 3/16th oz of bismuth using Longshot in Cheddite hulls and WAA12R wads. About 1/5 turned out to be bloopers. When I cut down the remaining shells, I found that most or even all of the powder had migrated up into the compression section of the hull. Whether this happened while in my pockets or in reloading I don't know, but I suspect the latter. When the wad is seated a lot of air has to be expelled, obviously. I think that is when the powder gets blown up above the powder cup. In any event, I was warned of powder migration but chose to ignore that based on finding published recipes for these loads. Just did not work for me.

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BrentD, (Professor - just for Stan)

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