.50 Beowulf

Moriarti AR-15 .50 Beowulf 16" Complete Upper Assembly | M-LOK | Heavy Barrel | Big Bore AR Upper

The Moriarti AR-15 .50 Beowulf 16" Complete Upper is designed for shooters who want maximum big-bore performance from a standard AR-15 platform. Featuring a heavy-profile 16-inch barrel, free-float M-LOK handguard, and custom muzzle brake, this upper is ideal for hunting, recreational shooting, and builders looking for serious stopping power in a compact AR15 platform.

Why Choose a 50 Beowulf AR Upper?

Few AR-15 cartridges deliver the authority of the .50 Beowulf (12.7x42). Designed to fire large-diameter projectiles from a standard AR-15 platform with the proper bolt and magazine configuration, the cartridge has become a favorite among hunters and enthusiasts looking for a true big-bore AR15.

The 16-inch barrel provides an excellent balance of maneuverability, velocity, and reliability while maintaining compatibility with most Mil-Spec AR-15 lower receivers.

Whether you're assembling a dedicated hunting rifle or simply want one of the most powerful AR-15 cartridges available, the Moriarti .50 Beowulf upper delivers dependable performance and premium USA-made components.

Features

Heavy-Duty 16" Barrel

• Caliber: .50 Beowulf / 12.7x42
• Length: 16"
• Heavy Profile
• 416 CMV Steel
• Parkerized Finish
• 1:20 Twist Rate
• Carbine-Length Gas System
• .936" Gas Block Journal
• 49/64x20 Muzzle Threads

Designed specifically for heavy .50 Beowulf projectiles while delivering reliable cycling and long service life.

Muzzle Brake

The included custom heavy muzzle brake helps reduce felt recoil and muzzle rise, allowing shooters to maintain better control of this powerful cartridge during rapid follow-up shots.

Forged Upper Receiver

• Forged 7075-T6 Aluminum
• Hardcoat Anodized
• Large Bore Design
• Forward Assist
• Dust Cover Installed

Provides a rugged, optics-ready foundation for your build.

Free-Float M-LOK Handguard

• 15" Slim Free-Float Rail
• Aircraft-Grade Aluminum
• M-LOK Accessory Slots
• Full-Length Top Rail
• Lightweight Design

Free-floating the barrel helps maximize accuracy while providing plenty of mounting space for optics, lights, bipods, and other accessories.

Built for Big Bore Performance

The .50 Beowulf is widely recognized for delivering tremendous energy from the AR-15 platform, making it a popular choice for:

• Hunting (where legal)
• Hog hunting
• Recreational shooting
• Big-bore enthusiasts
• Custom AR-15 builds

The heavy barrel and quality components help ensure dependable performance with this powerful cartridge.

Lower Receiver Compatibility

This upper is compatible with most Mil-Spec AR-15 lower receivers.

For optimal reliability, Moriarti recommends:

• 4.3 oz or heavier buffer
• Quality carbine recoil spring
• Proper .50 Beowulf bolt carrier group (6.5 Grendel BCG)

Compatibility

Included

• Complete Upper Receiver
• Barrel
• Gas System
• M-LOK Handguard
• Tri-Port Muzzle Brake

Not Included

• Bolt Carrier Group
• Charging Handle

Both are available separately.

Why Buy from Moriarti?

Every Moriarti upper is assembled using premium components and designed for builders who expect reliability, accuracy, and long-term durability.

Whether you're upgrading an existing rifle or starting a custom big-bore project, this upper provides an excellent foundation for your next build.

Key Takeaways

• 16" heavy-profile .50 Beowulf barrel
• Big-bore AR-15 platform
• Free-float M-LOK handguard
• Tri-port muzzle brake included
• Forged 7075-T6 upper receiver
• Compatible with Mil-Spec AR-15 lowers
• Recommended with a 4.3 oz or heavier buffer
• Made in the USA

Frequently Asked Questions

What is the .50 Beowulf designed for?

The .50 Beowulf is a big-bore AR-15 cartridge developed to deliver substantial energy from a standard AR-15 platform using compatible components.

Is this a complete upper assembly?

Yes. It includes the assembled upper receiver, barrel, gas system, handguard, and muzzle brake. The Bolt Carrier Group and Charging Handle are sold separately.

What lower receiver does this upper fit?

This upper is compatible with most Mil-Spec AR-15 lower receivers.

Does a .50 Beowulf require a special buffer?

For optimal cycling, Moriarti recommends using a 4.3 oz or heavier buffer with a quality carbine recoil spring.

What twist rate does the barrel use?

The barrel features a 1:20 twist, designed for stabilizing heavy .50 Beowulf projectiles.

Is this upper suppressor ready?

The barrel features 49/64x20 muzzle threads, allowing compatibility with muzzle devices designed specifically for the .50 Beowulf platform.

Is this upper good for hunting?

Yes. The .50 Beowulf is popular among hunters pursuing hogs and other appropriate game where legal. Always check local hunting regulations.

Does this upper include a BCG?

No. The Bolt Carrier Group and Charging Handle are sold separately.

What magazine does a .50 Beowulf use?

Most .50 Beowulf platforms use 50 cal AR-15 magazines designed or configured for the cartridge.

Is this upper made in the USA?

Yes. Moriarti Armaments assembles this upper using premium USA-made components.