Brownells 733 C7 5.56 Upper Receiver, 11.5'' 1-7 Twist Black

The Brownells 733 C7 5.56 upper receiver is a rifle-length upper for builders and gunsmiths assembling an AR-platform rifle in 5.56 NATO. This Brownells-branded upper features an 11.5-inch barrel with a 1-in-7 twist rate — a classic carbine-length profile that balances handling agility with velocity and accuracy potential. The 1-7 twist stabilizes a wide range of 5.56 loads, from 55-grain varmint rounds to heavier 77-grain match ammunition, making it genuinely versatile for hunting, sport shooting, or duty use.

Chambered in 5.56 NATO and finished in black, this upper receiver is stripped and ready for your preferred rail system, charging handle, and bolt carrier group. Whether you're building a compact hunting rifle, a short-barreled home-defense AR, or a precision 3-gun setup, the 11.5-inch length delivers a platform that's quick to shoulder without sacrificing ballistic performance. The 1-7 twist is reliable across mainstream ammunition weights, so you won't need to guess whether a new load will stabilize.

Brownells uppers are a no-nonsense choice for builders who want quality AR components without the manufacturer markup. This one's straightforward: good steel, tight tolerances, and the dimensions you need to complete your build. If you're familiar with AR assembly, this goes together with standard tools and parts. If you're new to the platform, pair it with a quality lower and a known-good bolt carrier for a system you'll trust.

Key Features

• 11.5-inch barrel — carbine-length profile for compact handling and velocity
• 1-in-7 twist rate — stabilizes 55-grain to 77-grain 5.56 ammunition
• 5.56 NATO chamber — widespread ammo availability and reliability
• Black finish — durable and low-profile
• Stripped upper receiver — ready for rail, charging handle, and BCG of your choice

Specifications

Frequently Asked Questions

Will this upper work with standard AR lower receivers?

Yes. The Brownells 733 C7 upper receiver is compatible with any mil-spec AR-15 lower receiver, whether you're using a commercial Brownells lower, a Colt, an Anderson, or a quality clone. The upper and lower interface is standardized across the AR platform.

What ammunition does the 1-in-7 twist stabilize?

A 1-in-7 twist is a workhorse rate that reliably stabilizes 5.56 ammunition ranging from 55-grain varmint/target loads through 77-grain match and hunting rounds. This makes it one of the most versatile twist rates for shooters who run a variety of ammunition types.

What comes with this upper receiver?

This is a stripped upper receiver — it includes the forged upper receiver itself, finished and ready to assemble. You'll need to source a charging handle, a rail or handguard, and a bolt carrier group separately to complete the build.

Is this suitable for hunting or just target shooting?

The 11.5-inch, 1-in-7 combination is solid for hunting as well as range work. The shorter barrel is nimble in thick cover or tight spaces, and the 1-in-7 twist gives you flexibility to use heavier, more effective hunting loads if needed. Many hunters and tactical shooters prefer this profile for practical rifle work.