I had a 12% tin mix(pewter) that I casted two months ago. A couple days after casting my alloy mix tested 13.4 BH. I tested it yesterday and it dropped to 10.4 BH. Three points in two months time? Isn't that a little drastic? I tested several boolits both a couple days after casting 2 months ago and yesterday all with the same variances.
Is this common when using a high volume of tin/pewter in alloy mixes?
