Fiocchi Ammunition Defense Dynamics, 357 Magnum, 158 Grain, Jacketed Hollow Point, 50 Round Box 357B Serious defense practitioners understand that personal safety requires 24/7 vigilance in all environments. From deep concealment micro pistols and snub-nose revolvers for discrete public carry to defensive rifles and shotguns in the home or on the road. Filling all those magazines and cylinders with reliable-performing defensive ammunition can be expensive, especially when dealing with multiple calibers and chamber gauges. With a focus on jacketed and semi-jacketed hollow points, buckshot, and slugs, the Defense Dynamics line delivers professional results for price-conscious defensive ammunition.