Federal Varmint & Predator Speer 17 HMR 17gr TNT HP Rimfire Ammo - 50 Rounds. When you rely on rimfire for putting down distant varmints, reach for Federal Premium Speer TNT. The bullet's thin jacket results in explosive performance on impact, and its reliable priming and propellant provide extremely consistent ballistics. Extreme accuracy Explosive expansion on impact Speer TNT bullet design Reliable priming and propellant Caliber: 17 HMR Grains: 17 Muzzle Velocity: 2530 Rounds Per Box: 50 Muzzle Velocity: 2530 fps Speer TNT Hollow Point