HM Defense MonoBloc Upper — .223 Rem / 5.56×45mm NATO, 9.50" Black Cerakote Barrel, 7075-T6 Aluminum Receiver, 8.50" M-LOK Free-Float Handguard (95MBUP556 | 854164007227)

Build a compact, hard-hitting AR-15 pistol or SBC-compliant carbine with the HM Defense MonoBloc Upper (Model 95MBUP556 | UPC 854164007227). This purpose-built upper assembly pairs a stout 9.50" Black Cerakote barrel chambered in .223 Rem / 5.56×45mm NATO with a rugged 7075-T6 aluminum black-anodized receiver and an 8.50" M-LOK free-float handguard for accessory modularity. The MonoBloc design delivers durability, slim ergonomics, and the mounting versatility competition shooters, operators, and serious AR builders demand.

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Product Overview

The HM Defense MonoBloc Upper is a complete upper receiver assembly engineered for short-barrel AR-15 platforms and pistol builds. The combination of a heat-resistant Cerakote-finished 9.50" barrel, aircraft-grade 7075-T6 aluminum receiver, and a low-profile 8.50" free-float M-LOK handguard creates a strong, lightweight package that excels in close-quarters handling while retaining the ballistic advantages of the .223/5.56 family.

This upper is ideal for range-oriented shooters, close-quarters drills, truck gun builds, and compact defensive platforms where maneuverability and accessory adaptability matter.

Key Features & Benefits

• Chambered for .223 Rem / 5.56×45mm NATO — Reliable feeding and broad ammunition selection for training, duty, or defensive use.

• 9.50" Black Cerakote Barrel — Durable corrosion-resistant finish increases longevity and provides a tactical matte appearance. Short length balances maneuverability with effective terminal performance for the caliber.

• 7075-T6 Aluminum Black-Anodized Receiver — Aircraft-grade material provides high strength-to-weight ratio and robust service life. The black anodize offers corrosion protection and a professional finish.

• 8.50" M-LOK Free-Float Handguard — Lightweight, rigid free-float design improves accuracy potential by eliminating external contact with the barrel and offers multiple M-LOK attachment points for lights, grips, bipods, and rail sections.

• Monobloc Styling & Fit — Precision machining yields tight tolerances and smooth compatibility with mil-spec lower receivers. Designed for straightforward installation on standard AR-15 lowers.

• Low-Profile Aesthetics — Slim handguard and clean receiver lines reduce snag points and improve handling in confined spaces.

• Accessory Ready — Top Picatinny rail for optics, back-up sights; M-LOK slots for mission-specific kit.

• Versatile Use Cases — Ideal for AR-15 pistol builds, compact home defense platforms, close-quarters training, and truck/vehicle setups.

Specifications

• Model: HM Defense MonoBloc Upper

• Part Number / SKU: 95MBUP556

• UPC: 854164007227

• Caliber: .223 Rem / 5.56×45mm NATO

• Barrel Length: 9.50 inches

• Barrel Finish: Black Cerakote (corrosion-resistant)

• Upper Receiver Material: 7075-T6 Aluminum (Black Anodized)

• Handguard: 8.50" Free-Float M-LOK

• Rail: Continuous Top Picatinny for optics/sights

• Intended Platform: AR-15 pistol or short-barreled AR builds (requires compliant lower/registration per local law)

• Compatibility: Standard mil-spec AR-15 lower receivers and components (verify before installation)

• Intended Use: Range, duty, defensive, competition, compact builds

Installation & Compatibility

The MonoBloc Upper is engineered to mate with standard mil-spec AR-15 lowers. Basic armorer knowledge and tools are recommended for installation. Key points:

• Verify lower receiver compatibility and that the lower is configured and legal for the intended upper (SBR laws vary by jurisdiction).

• Use a qualified gunsmith if you are not experienced with AR-15 assembly and function checks.

• Ensure proper headspace and follow torque specs for barrel nuts, castle nuts, and handguard hardware where applicable.

• Install quality optics, iron sights, and accessories on the top rail and M-LOK slots to match your mission profile.

Performance & Handling

Short-barrel rifles and pistols built with the HM Defense MonoBloc Upper deliver agile handling and fast target transitions. The free-float handguard helps maintain consistent harmonics and improves repeatable accuracy potential compared with keyed or contact handguards. The Cerakote barrel finish offers additional protection for high-round-count use and tough environmental exposure.

Maintenance & Care

• Cleaning: Clean bore and chamber after shooting sessions using proper .223/5.56 bore tools and solvents.

• Surface Care: Wipe exterior metal surfaces with a lightly oiled cloth after exposure to moisture. The Cerakote finish increases corrosion resistance but periodic maintenance preserves appearance.

• Inspection: Inspect handguard fasteners, rail mounting hardware, and gas system components regularly for security and function.

• Servicing: If any unusual wear, looseness, or failure is observed, discontinue use and consult a qualified armorer.

Safety & Legal Reminder

Always follow safe firearms handling practices — treat every firearm as loaded and keep muzzle direction and trigger discipline a top priority. This upper is intended for lawful firearm use only. AR-15 pistol and short-barrel configurations may be regulated in your jurisdiction; verify and comply with all federal, state, and local laws (including NFA regulations for Short-Barreled Rifles in the United States) before building or operating this upper on any lower receiver. If unsure, consult a licensed gunsmith or legal authority.

Who Should Choose the HM Defense MonoBloc Upper?

• Shooters building compact AR-15 pistols or SBRs (where legally permitted).

• Operators and instructors who want a maneuverable platform for close-quarters work.

• Competition shooters seeking lightweight, modular uppers for limited stages.

• Enthusiasts who value a durable Cerakote barrel and aircraft-grade receiver material for long-term reliability.

SEO-Focused Summary

The HM Defense MonoBloc Upper (95MBUP556 | 854164007227) is a compact, high-quality AR-15 upper assembly featuring a 9.50" Black Cerakote barrel, 7075-T6 aluminum black-anodized receiver, and an 8.50" free-float M-LOK handguard. Chambered for .223 Rem / 5.56×45mm NATO, this upper is built for maneuverability, modularity, and rugged use — perfect for AR-15 pistol builds, short-barrel applications (subject to law), and mission-oriented rifles where size and versatility matter. Pair it with a compliant lower, quality optics, and mission-specific accessories to create a compact platform that performs.

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