You want to build an AR-15 – but that doesn’t necessarily mean you want to *build* an AR-15. If you’d rather not gather and piece together every little thing that goes into an upper, then you’ll love the time-saving power of Luth-AR’s 20″ 1:8-1/2 fractional twist Bull Barrel complete upper receiver assembly!

This assembly features a 20” Bull Barrel of the manufacturer’s own design. The .223 caliber threaded barrel is made of strong stainless steel and grants the stability requisite for good accuracy. So too does its fractional twist, which is sufficient or ideal for bullets weighing 50 grains and heavier.

This assembly also features Luth-AR’s Palm Handguard: a 15” free-float handguard with Picatinny top rail, M-LOK slots, and ergonomic triangular profile that rests real comfortably in the hands. A3 flattop receiver with bolt carrier, charging handle, forward assist and ejection port cover included!

Includes:
Palm Handguard (vented 15″ M-LOK slots with barrel nut)
20″ 1:8-1/2 fractional twist Bull Barrel (416 SS)
A3 upper receiver (assembled)
Fully assembled bolt carrier (.223)
Rifle-length gas tube
.936 gas block
Charging handle
A2 flash hider

Barrel Specs:
Length: 20″
Metal: 416 stainless steel
Thread pitch: 1/2x28
Gas block diameter .936
Gas port diameter: .097-.098″
Twist: 1:8-1/2” RH
Lands/grooves: 6
Feed ramp: M4
Button broached

Upper Specs:
7075-T6 aluminum
Hard coat anodize (black)

Bolt Specs:
Bolt: Carpenter 158 steel
Extractor: 4140 alloy steel
Army spec heat treatment
Manganese phosphate

Bolt Carrier Specs:
Carrier: 8620 steel
Cam pin: 4340 alloy steel
Carrier key: 4130 alloy steel
Army spec heat treatment
Manganese phosphate