Defense Dynamics Features Defense Dynamics cartridges are built with the same quality cases hulls powders and primers that experienced shooters have come to expect from Fiocchi ammunition while employing projectiles proven to deliver the kind of terminal performance you demand in a personal or home defense round. Defense Dynamics Specifications Caliber: 9mm Luger Model: Defense Dynamics Bullet Weight: 147 gr Rounds Per Box: 50 Casing Material: Brass Application: Personal Defense Bullet Type: Jacketed Hollow Point (JHP) Muzzle Energy: 310 ft lbs Muzzle Velocity: 975 fps