These five.45x39mm cartridges aspect cleanse-burning Berdan primers, Whole Metal Jacket (FMJ) projectiles, and cost-saving metal casings that happen to be coated with a light film of polymer. The polymer coating protects the metal circumstances from rust though in storage but additionally serves being a buffer concerning casings and chamber walls; https://tacticalrounds.com/product-category/handgun-ammo-for-sale/45-gap-ammo/