Re: Retumbo powder ????
Retumbo does seem to have the tendency to clump up after sitting. I have also found that when taking apart loads that were a few months old that the top 1/8" or so of the powder in the case had the granulals fused and had to be loosened with a small wooden dowel. However, it did not effect the accuracy or velocity readings of the loads. I think effect is inherent in the formulation.
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