Anyone tried Winchester StaBallHD yet? Right next to Retumbo on the burn rate chart.
Winchester StaBALL HD
Winchester® StaBALL™ HD is a temperature-insensitive, double-base, BALL® Powder, stable in extreme-hot or -cold conditions. This slow-burning magnum powder provides optimal loading density in large capacity magnum cartridges appropriate for the burn speed, which is ideal for 6.5 PRC, 7MM...
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