M4E1 5.56 Nato Assem Uppr Rcvr M4 10.5'' Bbl Carbine Black

The Aero Precision M4E1 5.56 NATO assembled upper receiver with 10.5\" barrel is a purpose-built carbine upper that bridges the gap between affordable mil-spec compatibility and custom-billet aesthetics. This is a complete, ready-to-mount upper assembly for AR-15 builders and shooters who want a short, handy rifle without compromising on build quality or modularity. It comes fully assembled except for the bolt carrier group and charging handle—exactly the components most builders want to select themselves anyway.

The receiver itself is forged from 7075 T6 aluminum and hardcoat anodized to mil-spec standards, so you get the durability of military-grade materials with the refined appearance of a billet design. The 10.5\" barrel is chrome-moly-vanadium steel with a 1-7\" twist, finished in black QPQ, and topped with a standard A2 flash suppressor. The carbine-length gas system uses a low-profile gas block tuned for this barrel length. The chamber accepts both 5.56 NATO and .223 Remington ammunition.

Mounted to the receiver is Aero's Gen 2 Enhanced M-LOK handguard, a full-length system that runs a Picatinny rail from the rear receiver across the entire handguard. M-LOK slots at the 3, 6, and 9 o'clock positions accept modern lightweight accessories, and QD sling mounts are integrated at those same stations. The handguard's 1.78\" inside diameter clears most common muzzle devices and suppressors up to 1.5\" diameter. Texture milling on the flat sides improves grip and adds visual character to the build.

This upper is ideal for short-range shooting, home defense builds, or compact carbines where barrel length and overall length matter. Pair it with a lower receiver of your choice and the bolt carrier group and charging handle you prefer to complete your custom AR.

Key Features

• Forged 7075 T6 aluminum receiver with mil-spec hardcoat anodize
• 10.5\" chrome-moly-vanadium barrel with 1-7\" rifling and black QPQ finish
• Carbine-length gas system with low-profile gas block
• Accepts 5.56 NATO and .223 Remington ammunition
• A2-style flash suppressor installed
• Gen 2 Enhanced M-LOK handguard with full-length Picatinny rail
• M-LOK accessory slots at 3, 6, and 9 o'clock positions
• Integrated QD sling mounts
• Textured grip flats for improved handling
• Completely assembled except bolt carrier group and charging handle

Specifications

Frequently Asked Questions

Is this upper receiver compatible with standard AR-15 lowers?

Yes. The M4E1 uses standard mil-spec pivot and takedown pin holes (0.250\" diameter) and will work with any AR-15 lower receiver that accepts a standard upper.

What's the overall length of a rifle built with this upper?

With the 10.5\" barrel and A2 flash suppressor, the overall length is approximately 9\" to 10" depending on your lower receiver and buttstock setup. This is a compact carbine configuration.

Does this come with a bolt carrier group and charging handle?

No. The upper receiver assembly is complete and ready to mount, but does not include the bolt carrier group or charging handle. You'll need to source those separately to complete your build.

Can I suppress this rifle?

Yes. The handguard's 1.78\" inside diameter will clear most suppressors up to 1.5\" in diameter. You'll need to source a suppressor and determine your local legal requirements before installation.