Brownells 75th Anniversary - A Shooting Heritage

Take Care of the Environment While Taking Out Your Target

Underwood Ammo’s lead free, solid copper, precision CNC Xtreme Penetrator rounds come ready to pack a real punch in your .450 Bushmaster. Featuring a specially designed nose, the Underwood Ammo Xtreme Penetrator increases the hydraulic velocity inside the target, creating massive pressure spikes and an even bigger permanent wound cavity.

The Underwood Ammo Xtreme Penetrator features deep penetration too, going in more than double than most expanding bullets. The blunt nose of the Xtreme Penetrator round ensures reliable feeding from the magazine, too.

  • Bullet weight: 245 grains
  • Muzzle velocity: 2,260 fps
  • Muzzle energy: 2,778 ft/lbs
  • 20 rounds per box

Your target had better start running when you take the field with Underwood Ammo’s Xtreme Penetrator.

You must be 18 or older to purchase shotgun or rifle ammunition and 21 or older to purchase handgun ammunition. All ammunition must be shipped Domestic Ground. Shipping not available for International residents. Residents in CA, DC, IL, MA, NY, CT, and NJ may have additional restrictions. Always make sure you use the correct ammunition for your firearms. Check your state and local laws for any other applicable firearms and ammunition regulations. Due to Department of Transportation regulations, we cannot accept returns on ammo. Please check local laws before ordering. View full restrictions here.

Ammunition pricing is per box.

ATTENTION – California Customers
Brownells is still shipping ammunition orders to California but the process has changed to comply with California Proposition 63. We must now ship ammunition purchased online to an FFL or California-approved ammunition dealer. After placing your order, a Brownells representative will contact you to ensure your ammunition arrives quickly and in compliance with the law.


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