Hornady Frontier 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition 20 Rounds. Specifications for Hornady Frontier 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition: Manufacturer: Hornady Caliber: 5.56x45mm NATO Bullet Type: Full Metal Jacket (FMJ) Bullet Weight: 55 grain Cartridge Case Material: Brass Muzzle Velocity: 3240 ft/s Muzzle Energy: 1282 ft-lbs Application: All Purpose Package Type: Box Primer Style: Centerfire Sectional Density: 0.157 G1 Ballistic Coefficient: 0.243 Features of Hornady Frontier 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition: Consistency In Every Cartridge: State-of-the-industry loading techniques and quality control procedures ensure the reliability of every Frontier Cartridge round. Rounds For All Applications: Frontier Cartridge offers ammunition configured for a wide range of shooters and applications everything from plinking target shooting and hunting to law enforcement training and self-defense. Brass Cases: In addition to Hornady target friendly non-steel core bullets in a variety of offerings Frontier Cartridge features brass cartridge cases and military-grade boxer primers and propellant. Package Contents: Hornady Frontier 5.56x45mm NATO 55 grain Ball (M193) Full Metal Jacket (FMJ) Brass Centerfire Rifle Ammunition What is Hornady Frontier 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition good for? The manufacturer thinks that it is best for all purpose.Hornady FR200: Frontier 5.56x45mm NATO 55 grain Full Metal Jacket Brass Cased Centerfire Rifle Ammo 20 Rounds