This cartirdge is great for training and range use. We use a 158 grain TPJ (Total Polymer Jacket) bullet that we make in-house. The lead cast, polymer jacketed bullet prevents lead to bore contact. Traditional copper jacketed bullets mean metal to bore contact, which wears your barrel faster than polymer. These bullets are also safer for shooting steel targets. The polymer jacket also eliminates lead exposure for your hands, and in the air around you.