If you want to shoot lead in the Glock barrel, you will need to use "hard cast" lead and stay away from "swaged" lead. The 1 in 10 trust rate is too fast for soft lead. The KKM is a 1 in 16 twist rate. With lead, slower velocity (900 or less) is better, ergo: the 135 grain and bigger is best for lead bullet use. A coated bullet is better that a wax only bullet. The Bayou bullet are about as good as they get.