True Velocity .308 Winchester 165 Grain Sierra GameKing Rifle Ammo is precision-engineered, polymer-cased ammunition to allow for big improvements over brass-cased ammunition. This composite-cased ammo is much lighter, reduces heat transfer to your firearm, and is optimized for use in bolt-action rifles. True Velocity offers less deviation in velocity, which gives you improved accuracy. More efficient powder burn also decreases your muzzle flash. True Velocity ammo is not designed for reloading in commercial-grade reloading equipment. 165-grain Sierra GameKing bullets Polymer-cased ammo 30% lighter than loaded brass Optimized for use in bolt-action rifles Increased accuracy Consistency in muzzle velocity Reduced heat transfer Magnetic retrieval