M4E1 Assembled Gen 2 Upper 14.7 Mid Pencil Length

Feature-Rich Tactical Carbine Upper Without the Excess Weight

Aero Precision’s M4E1 5.56mm Pencil Barrel Mid-Length Upper Receiver replicates the feature set of their standard M4E1 mid-length carbine with one "addition by subtraction": a narrow-diameter "pencil" barrel that saves weight. The result is ready to form the top half of a lightweight, fast-handling tactical carbine that doesn’t skimp on extra features.

The M4E1 5.56mm Pencil Barrel Mid-Length Upper Receiver comes fully assembled, lacking only a bolt/carrier group and charging handle, two components customizers typically replace any way. "Mid-Length" refers to the gas tube, which is longer than the standard carbine tube to slow down gas velocity and improve reliability in cycling. It’s available with a 14.7" or 16" barrel - see Gun Tech Note below.

• 4150 chrome-moly-vanadium barrel, 1-7" rifling, black QPQ finish
• Chambered for 5.56x45 NATO; accepts .223 Remington, too
• MID-LENGTH gas system
• A2-style flash suppressor installed - NOT pinned or welded
• 1/2"-28 tpi muzzle threads
• Forged 7075 T6 aluminum receiver, Mil 8625 Type 3 Class 2 hardcoat anodized
• Ejection port cover & forward assist installed
• .250" dia. pivot/takedown pin holes
• Handguard: 1.78" inside diameter clears most muzzle devices and 1.5" suppressors
• Bolt/carrier group & charging handle NOT included
• All NFA rules apply

The M4E1 5.56mm Pencil Barrel Mid-Length Upper Receiver comes with Aero Precision’s latest Gen 2 Enhanced M-LOK Handguard installed. Receiver and handguard form a rock-solid, monolithic assembly with a full-length Picatinny top rail, and plenty of attachment points for M-LOK-accessories. QD sling swivel sockets at the 3/6/9 o’clock positions. The extended handguard covers the low-profile gas block. Texture milled into the flats give you an enhanced grasping surface - plus, they add to your gun’s unique appearance.

Brownells Gun Tech™ Note: The M4E1 5.56mm Pencil Barrel Mid-Length Upper Receiver is available with a 14.7" or 16" barrel. The flash suppressor on the 14.7" barrel is not pinned or welded in place. Per the National Firearms Act, the muzzle device MUST be pinned and welded to achieve the minimum 16" OAL for a civilian rifle build. The 16" barrel has sufficient length to meet NFA requirements without permanently attaching the flash suppressor.