Tromix 16.25" 458 SOCOM Complete Upper with BCG and CH - 15" M-Lok Rail

16.25" 458 SOCOM Complete Upper for AR-15 with Genuine Tromix Barrel and Bolt, BCG, Charging Handle and 15" M-LOK Rail

This 16.25" 458 SOCOM complete upper features a genuine Tromix chrome moly HBAR barrel and genuine Tromix .458 SOCOM bolt assembly, pairing two components specifically designed for the .458 SOCOM platform. The Tromix bolt is combined with an M16-profile nitride carrier, while a carbine-length gas system, 15" free-float M-LOK handguard, compensator, and AR-15 Mil-Spec 7075 aluminum charging handle complete the assembly. The genuine Tromix bolt is professionally headspaced with the Tromix barrel using Manson GO and NO-GO gauges before the complete upper leaves Ballistic Barn in Texas.

Quick Glance:

Caliber: .458 SOCOM
Platform: AR-15
Configuration: Complete Upper with BCG and Charging Handle
Barrel Length: 16.25 inches
Barrel Manufacturer: Genuine Tromix
Barrel Material: Chrome Moly
Barrel Profile: HBAR
Barrel Finish: 2400 Series Bake-On GunKote
Twist Rate: 1:14
Barrel Extension: Standard AR-15 Big Bore Barrel Extension with Single Feed Ramp
Muzzle Threads: 5/8x32
Gas System: Carbine Length
Gas Block: .875" Low Profile - Manganese Phosphate Finish
Handguard: 15" Lightweight Free-Float M-LOK Rail
Upper Receiver: Big Bore Forged 7075-T6 Aluminum
Muzzle Device: Compensator with Crush Washer
Bolt: Genuine Tromix .458 SOCOM Bolt Assembly - 9310 Steel
Bolt Carrier Group: Included - M16 Profile Nitride BCG with Genuine Tromix Bolt
Charging Handle: Included - AR-15 Mil-Spec 7075 Aluminum
Headspace: Tromix Bolt Professionally Headspaced with Tromix Barrel Using Manson GO and NO-GO Gauges
Assembly: Fully Assembled Complete Upper Receiver

Full Details:

Big Bore Upper Receiver:
The AR-15 big bore upper receiver is forged from 7075-T6 aluminum and includes the forward assist and dust cover assembly installed. It features a matte black hardcoat anodized finish meeting MIL-A-8625 Type III Class 2 specifications.

Genuine Tromix 16.25" 458 SOCOM Barrel:
At the center of this 458 SOCOM complete upper is a genuine Tromix 16.25" chrome moly HBAR-profile barrel designed specifically for .458 SOCOM. The barrel features a 1:14 twist rate, 5/8x32 muzzle threads, and a 2400 Series Bake-On GunKote exterior finish. A standard AR-15 big bore barrel extension with a single feed ramp completes the barrel configuration.

15" Free-Float M-LOK Handguard:
The upper features a lightweight 15" extended rifle-length narrow-profile free-float M-LOK handguard machined from 6061 aluminum. M-LOK mounting slots run along the 3, 6, and 9 o'clock positions, providing mounting space for compatible accessories. The handguard features a matte black hardcoat anodized finish meeting MIL-A-8625 Type III Class 2 specifications.

Carbine-Length Gas System:
The genuine Tromix 16.25" barrel is configured with a carbine-length gas system and .875" low-profile gas block with a manganese phosphate finish.

Compensator:
The 5/8x32 threaded muzzle is fitted with a compensator and crush washer.

Genuine Tromix Barrel and Bolt:

This 458 SOCOM complete upper combines a genuine Tromix barrel with a genuine Tromix .458 SOCOM bolt assembly. Tromix specializes in .458 SOCOM components, and its bolt incorporates design features developed specifically for the cartridge to address common feeding and cycling issues encountered with .458 SOCOM systems. Pairing the Tromix bolt with a genuine Tromix barrel provides a purpose-built barrel and bolt combination rather than relying on generic big-bore components.

Genuine Tromix .458 SOCOM Bolt Carrier Group:

The included M16-profile nitride bolt carrier group is equipped with a genuine Tromix .458 SOCOM bolt assembly designed specifically for the cartridge.

Genuine Tromix Bolt:
The Tromix bolt is machined from a single piece of aircraft and bearing-quality 9310 alloy steel. It is properly heat-treated, precision ground, shot-peened, MPI tested, and finished with a manganese phosphate coating. The bolt is professionally headspaced with the genuine Tromix barrel installed in this complete upper.

M16-Profile Nitride Carrier:
The M16-profile carrier is machined from aircraft and bearing-quality 8620 steel, properly heat-treated, precision ground, and finished with nitride for surface durability and corrosion resistance.

Enhanced Extractor:
The BCG features a one-piece billet, fully machined enhanced extractor with a phosphate coating for durability and reliable extraction.

Firing Pin, Cam Pin and Ejector:
The firing pin is machined from 8740 steel, precision ground, and chrome plated. The BCG also features a nitride cam pin along with an S7 tool steel ejector and extractor retaining pin for strength and durability.

Gas Key:
The 4130 steel gas key features a nitride finish and is precision staked using a hydraulic staking machine. Grade 8, properly heat-treated carrier key screws with T25 drives provide secure fastening.

Charging Handle:
The included AR-15 Mil-Spec charging handle is precision machined from lightweight and durable 7075 aluminum for dependable operation and long service life.

Professional Headspacing:

The genuine Tromix .458 SOCOM bolt is professionally headspaced with the genuine Tromix barrel using Manson GO and NO-GO gauges. The bolt and barrel are checked together before the complete upper leaves Ballistic Barn in Texas.

Ready to Install:

This 16.25" 458 SOCOM complete upper arrives fully assembled with the genuine Tromix barrel, M16-profile nitride BCG with genuine Tromix .458 SOCOM bolt, and AR-15 Mil-Spec 7075 aluminum charging handle. It is designed for use with compatible standard-dimension AR-15 lower receivers.

Important: This complete upper receiver assembly is not a firearm and can be shipped directly to you. No FFL is required.

Ballistic Barn AR-15 complete uppers are assembled in Texas using quality AR-platform components. Each complete upper is individually inspected, and the included bolt is professionally headspaced with its barrel before shipment to help provide proper fit and dependable operation.