Hornady Gmx Bullets 25 Cal .257 90 Gr GmxHard-hitting and deep-penetrating, the GMX® bullet combines monolithic construction with pioneering ballistic design to meet the need for a premium, non-traditional bullet. Tougher than pure copper, the mono-metal copper alloy has been proven to shoot cleaner, foul less, and deliver consistent, even pressure curves. The tough alloy material routinely retains 95% or more of its original weight and expands up to 1.5 times its original diameter.Featuring a long, sleek profile with cannelures, the design reduces overall bearing surface and drag, while achieving some of the highest ballistic coefficients from monolithic, non-traditional bullets. Initiating expansion upon impact, the hard polymer tip drives into the hollow cavity at the front of the bullet, creating a mushroom-style projectile as it travels through the animal. Fully California compatible and appropriate for use in areas requiring the use of non-traditional bullets, GMX® is ideal for any sized game, from antelope to moose.