Hornady Superformance GMX Ammunition 5.56x45mm NATO 55 Grain GMX Boat Tail Lead-Free Box of 20

Product #: 387671 Hornady #: 81254 UPC #: 090255812541
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SUPERFORMANCE ammunition is loaded with proprietary propellants that increase the velocity ratings up to 200 feet per second compared to other popular brands. Because there is no increase in pressure, regardless of the caliber, there is no increase in felt recoil but there IS an increase in efficiency and high speed performance. From sub-zero arctic temperatures to almost unbearable desert heat, SUPERFORMANCE ammunition can withstand any hunting habitat.

Hard-hitting and deep-penetrating, the GMX bullet combines monolithic construction with pioneering ballistic design to meet the need for a premium, non-traditional bullet. The mono-metal design of the GMX bullet is crafted from a copper alloy. Harder than solid copper, the copper/zinc 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 the bullet’s 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 other areas requiring the use of non-traditional bullets, GMX is ideal for any sized game, from antelope to moose. This ammunition is new production, non-corrosive, in boxer primed, reloadable brass cases.

Please Note: While the 5.56x45mm  will fit in a .223 Remington chamber, the 5.56 is a military round that runs at higher pressures than its .223 counterpart and is not recommended to be fired in a .223 Remington chamber.

Technical Information

  • Caliber: 5.56x45mm NATO
  • Bullet Weight: 55 Grains
  • Bullet Style: GMX
  • Case Type: Brass

Ballistics Information:

  • Muzzle Velocity: 3130 fps
  • Muzzle Energy: 1196 ft. lbs.

Product Videos

  • Hornady Video
  • Hornady Video
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