Accurate description recipe find here
http://mx5-kevin.blogspot.com
More info in the amateur Pyrotechnics and chemistry forum: http://pyroprojektek.org/index.php?/blogs/entry/6-toturialhow-to-make-professional-firecrackers-from-household-materials
K2S2O8 Mg Na2S2O8 Potassium persulphateor Sodium persulphate,+Magnesium or magnelium MgAl powder the powerful Kclo4 alternative in flash powders.Ratio 1/1 K2S2O8+Mg