Federal American Eagle, 357SIG, 125 Grain, Full Metal Jacket, 50 Round Box AE357S2 Experience a cleaner way to shoot. The exclusive polymer coating in Syntech range ammunition prevents harsh metal-on-metal contact between the bullet and bore, eliminating copper and lead fouling. Combined with clean-burning powders and the Catalyst lead-free primer, Syntech loads keep your gun cleaner, longer, so you can shoot more-and shoot better.