12.7×42 (50 cal Beowulf) Complete Upper receiver with 10.5″ barrel
This 12.7×42 Complete Pistol Upper Receiver (.50 cal Beowulf) is built by J-5 Tactical using quality AR parts. This is a complete, AR-15 12.7×42 pistol upper receiver that is fully assembled and will perform without hesitation. All J-5 Tactical 12.7×42 .50 cal Beowulf Complete Upper Receivers are tested prior to shipping. Trust J-5 Tactical Supply to provide you with a quality 12.7×42 .50 cal Beowulf Complete Upper Receiver.
1 – Complete BIG BORE upper receiver * larger ejection port, with forward assist.
1 – 10 1/2 inch parkerized 12.7×42 barrel
1 – 9 inch M-LOK free floating hand guard and barrel nut
1 – Helius Tactical Muzzle Brake
1 – Micro .936 gas block
1 – Stainless steel gas tube (pistol length)
1 – Bolt Carrier Group
1 – Mil-Spec Charging handle
*We test fire with the Lancer and properly modified GI mags.
*There maybe slight variations in hand guard style depending on current stock and availability*
The .50 Beowulf is an elephantine round designed to increase stopping power of an AR-15-platform rifle by a factor of 10 billion or so. The cartridge is just short enough to fit in a standard AR magazine, although for obvious reasons (it’s fat) it won’t double stack like .223 Rem./5.56 NATO cartridges. Developed by Alexander Arms, this cartridge is a tapered, straight-wall case topped with, you guessed it, a .50-caliber projectile. So that it can use a 7.62×39 mm bolt face, the case rim is rebated, or smaller than the case body. This not only allows use of a “more standard” bolt, but it also allows that bolt to have enough metal on it to withstand pressure over time and use.