over 2,000 feet per second). At rifle velocities, a hollow point is not needed for reliable expansion and most rifle ammunition makes use of tapered jacket designs to achieve the mushrooming effect. At the lower handgun velocities, hollow point designs are generally the only design which will expand reliably. Modern hollowpoint bullet designs use many different methods to provide controlled expansion, including: Jackets that are thinner near the front than the rear to allow easy expansion at the beginning, then a reduced expansion rate. Partitions in the middle of the bullet core to stop expansion at a given point. Bonding the lead core to the copper jacket to prevent separation and fragmentation. Fluted or otherwise weakened jackets to encourage expansion or fragmentation. Posts in the hollow cavity to cause hydraulic expansion of the bullet in tissue. While very effective in lightly clothed targets, these bullet types tend to plug up with heavy clothing materials that results in the bullet not expanding. Solid copper hollow points, which are far stronger than jacketed lead, and provide controlled, uniform expansion even at high velocities. Plastic inserts in the hollow, which provide the same profile as a full-metal-jacketed round (such as the Hornady V-Max bullet). The plastic insert initiates the expansion of the bullet by being forced into the hollow cavity upon impact. Plastic inserts in the hollow to provide the same profile for feeding in semiautomatic and automatic weapons as a full-metal-jacketed round but that separate on firing while in flight or in the barrel (such as the German Geco "Action Safety" 9 mm round) Mechanism When a hollow-point hunting bullet strikes a soft target, the pressure created in the pit forces the material (usually lead) around the inside edge to expand outwards, increasing the axial diameter of the projectile as it passes through. This process is commonly referred to as mushrooming, because the resulting shape, a widened, rounded nose on top of a cylindrical base, typically resembles a mushroom. The greater frontal surface area of the expanded bullet limits its depth of penetration into the target, and causes more extensive tissue damage along the wound path. Many hollow-point bullets, especially those intended for use at high velocity in centerfire rifles, are jacketed, i.e. a portion of the lead-cored bullet is wrapped in a thin layer of harder metal, such as copper, brass, or mild steel. This jacket provides additional strength to the