Hey boys, I have been using the Skenco,Goldenrod 8.5 grain and the Skenco match,6.4 grains. I too was just exprimenting. They shoot pretty good and I am convinced they penetrate a lot better than lead as they have a zinc(harder) head. I made dents in a stove burner(3/32" steel) with lead and holes with the skenco,both weights.But accuracy is not as precise as lead in my gun. Gamo,Viper.177. They do leave some plastic residue in the bore and I smell a faint burnt plastic smell after shootin.AKJC1977