I have always worked with coww or a mixture of coww/pure. I am getting into muzzleloaders, and was encouraged to use a 1:16 alloy. 2 questions, any real problem using pewter instead of tin at the same 1:16 ratio? 2nd question, at what velocity does the alloy stop reliably expanding? I am getting 1600 fps muzzle velocity (lee 452-300 with a sabot) and trying to figure out my max range. Thanks!