I believe this formula may be derived from a similar formula by Powley. Powley needs expansion ratios. I have tried Don Miller's formula with different gun specs and found very reasonable results until I tried BLE chrono results. The predicted Velocities are way over. All that means to me is sheutzen powder is very different from Geox 3f. The K Value for that powder seems to be 1050.
Last edited by mikthestick; March 16, 2012 at 04:50 AM.
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