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Tromix 458 SOCOM Upper 16" Barrel Assembly and Tromix Matched 458 Socom Bolt w/ Rifle Length Rail
Tromix 16" 458 SOCOM Complete Upper Assembly Rifle Length Rail

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List Price: $799.99
Our Price: $699.99
Savings: $100.00

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Product Code: 16458TU1X14MLMLR

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Tromix 458 SOCOM Upper 16" Barrel Assembly and Tromix Matched 458 Socom Bolt w/ Rifle Length Rail

*Milspec forged aluminum upper receiver with forward assist and dust cover assembly installed. Matte black hard coat anodized Mil 8625 Type 3 Class 2. One large single Feed Ramp for big bore cartridges. Forged from 7075 T6 aluminum. This receiver has been correctly modified around the ejection port to allow for clearance and proper ejection of the 458 SOCOM cartridge.

*12" Rifle Length Narrow Profile Free Float Rail. Very comfortable and very light weight. Your choice of Keymod or M Lok slots. Slots run the entire length of our rail at the 3, 6, and 9 o'clock postions. Picatiny rail sections NOT included but are available for purchase on our website if needed. Rail sections easily attach to our rails for adding accessories like bipods, flash lights, grips, lasers, etc.

*Tromix brand 16.25″ Barrel profile is .900″ under the hand guards, .875″ at the gas block, and .800″ at the muzzle. Carbine length gas system. Threaded 5/8-32 with a 1:14 twist. Machined for use with hand guards that don’t use a hand guard cap. Barrel weight: 1.92 lbs. 4150 Carbon Steel.

*Complete 458 Socom BCG Bolt Carrier Group built with a factory Tromix Matched bolt assembly.

*.875 low profile gas block.

*Carbine Gas Tube.

*Competition Muzzle Brake threaded 5/8x32

*It is HIGHLY recommended to run this upper with a D&H Tactical 458 Socom Magazine for zero feed issues. We have them available for purchase on our website.

*This upper assembly will fit all standard AR 15 lower receivers.

This item IS NOT A FIREARM!!! It is only "Firearm Parts", so no FFL is needed and it can be shipped directly to you. You are responsible for knowing your state or local laws. We will not ship this item to areas where it is not legal to own.



    .458 SOCOM rifles and upper halves should always be loaded from a magazine. Do not load singly through the ejection port, a slam fire can occur upon bolt release.

    .458 SOCOM rifles and upper halves should only be fed from aluminum magazines. Polymer magazines can swell and rounds can shift creating opportunities for misfeeds, jams, and other issues that don’t occur with the aluminum mags.

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