I tried the same cast bullet in my Swiss K31 rifle that I have had great luck with in my 30-30. I have fired almost a thousand rounds in the 30-30 with virtually no leading, but in the K31 after only 10 rounds I ended up with flakes coming out in the first cleaning patch. I was using a light load of Unique in both rifles. Any guesses why one leaded like crazy and the other didn't?