.50 Beowulf Underwood 12.7x42 350gr FMJ 20rds

The Underwood .50 Beowulf 350gr FMJ is a hard-hitting range load for one of the most capable big-bore AR-15 cartridges ever developed. Designed by Alexander Arms, the .50 Beowulf (also known as 12.7x42) transforms a standard AR-15 lower into a close-range powerhouse — delivering massive .50-caliber energy on target while using the same lower receiver, trigger, and magazine well as your standard 5.56 build.

The 350-grain Full Metal Jacket bullet is the go-to choice for range training, function testing, and high-volume shooting in your .50 Beowulf upper. FMJ construction provides reliable feeding and consistent performance round after round, making it ideal for breaking in a new upper, running drills, or simply enjoying the experience of shooting one of the most impressive AR-platform cartridges available.

Underwood Ammunition, based in Illinois, is known for loading to the upper end of safe pressure specs — delivering more velocity and energy than many competitors while maintaining strict quality control. 20 rounds per box.

• Caliber: .50 Beowulf / 12.7x42
• Bullet weight: 350 grain
• Bullet type: Full Metal Jacket (FMJ) — range and training load
• Compatible with Alexander Arms and other .50 Beowulf uppers on standard AR-15 lowers
• Reliable feeding and consistent performance
• 20 rounds per box
• Ideal for range use, function testing, and high-volume shooting

In-store purchase only. Ammunition is not available for online shipping. Available at Glenwood Springs Outdoors, 831 Grand Ave, Glenwood Springs, CO.