Hornady Superformance, 223 Remington, 50 Grain, Copper Alloy eXpanding Projectile, 20 Round Box 83292 Increase your rifle's performance up to 200 fps without extra chamber pressure, recoil, muzzle blast, temperature sensitivity, fouling, or loss of accuracy. Superformance uses progressive propellants that take your favorite V-MAX, NTX, SST, CX, and InterLock, bullets to levels of performance that are simply unattainable with conventional ammunition.