Nosler Trophy Grade 300 Remington Short Action Ultra Magnum Ammo 165 Grain Partition Spitzer ammo review offers the following information; Nosler Trophy Grade ammunition is high quality, production-run ammunition manufactured to strict tolerances and inspected as it is hand-packaged. Trophy Grade features Nosler Custom brass and the dependable, high performing bullets you know and trust. Partition Bullets feature a fully tapered jacket that 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 or low velocities. Nosler's integral partition supports the expanded mushroom and retains the rear lead alloy core. The enclosed rear core retains more than half the original bullet weight for deep penetration. The special crimp locks in the rear core section, adding strength to resist deformation under the pressure of heavy magnums.

Partition has two separate lead cores with a solid partition between them.