Caliber: 308 Winchester – Bullet Weight: 165 Grains – Bullet Style: SST – Case Type: Brass – Muzzle Velocity: 2840 fps – Muzzle Energy: 2955 ft. lbs. – Rounds Per Box: 20 – Superformance ammunition is 100 to 200 fps FASTER than any conventional ammunition on the market today and achieves this performance in EVERY gun WITHOUT increases in felt recoil muzzle blast temperature sensitivity fouling or loss of accuracy. Superformance is a cutting edge technological advancement in ammunition design that transcends convention and achieves the highest performance of any ammunition on the market today.