Here is our experiment with Blue Dot. Onty.

http://www.thehighroad.org/showthread.php?s=&threadid=88893

I have shot Blue Dot in my .41 & .44 Mags and never with such a problem as you described. I use it for what would probably be considered a light load with light bullets: 12 gr. with 200 gr bullets and 13 gr with 220 gr bullets respectively. Slim