Nosler Engineering: Nosler's special lead-alloy, dual-core provides superior mushrooming characteristics at virtually all impact velocities; Fully Tapered Copper-Alloy Jacket: Ruptures instantly at the thin jacket mouth, yet the gradual thickening along the bullet's axis controls expansion and curls the jacket uniformly outward at high and low velocities; Nosler's Integral Partition: Supports the expanded mushroom and retains the rear lead-alloy core. The enclosed rear core retains more than two-thirds of the original bullet weight for deep penetration; Dual-Core Construction: Every Partition bullet in the Nosler line delivers optimum length, weight and ogive design for maximum in-flight and terminal performance; Special Crimp Locks: Adds strength to resist deformation under the pressure of heavy magnums