Nosler Trophy Grade, 243 Winchester, 100 Grain, Partition, 20 Round Box 61046 Nosler Trophy Grade ammunition is loaded with the Nosler Partition bullet - the benchmark for hunting bullets since 1948 and the cornerstone upon which the entire company was founded. The bullet's dual-core design assures rapid expansion of the foremost core while Nosler's integral partition supports the expanded mushroom allowing the enclosed rear core to remain intact retaining more than two-thirds the original bullet weight for deep penetration. Tried and true, Nosler's Trophy Grade ammunition provides undeniable reliability on all game.