This upper receiver assembly features the POF's M Rail, the E2 Chamber Feature, two 5-slot detachable rail sections, and one 12-slot detachable rail section. It has a 16.5" hand-lapped, button-twisted, rifled heavy contour barrel with fluting to reduce weight and heat. The barrel is made from 4150 Mil-B-11595 chrome-moly-vanadium alloy (machine gun rated) and is 70 Rockwell case hardened (Nitride) heat-treated with a corrosion-resistant, 10x thicker, 10x harder than MIL-SPEC, chrome lining. It features POF-USA's C.R.O.S. (Corrosion Resistant Operating System) with the nitrided barrel, single-piece gas block, nitride heat-treated gas plug, chromed gas piston, and NP3 coated bolt carrier assembly (one-piece) all billet machined. It has a heat-treated, chrome-plated bolt, NP3-coated roller cam pin, and a nickel-plated 8620 chrome-moly-steel, integral keyed, bolt carrier (billet machined), heat treated/plated per MIL-SPEC. It is gas piston operated with a rotating bolt (short stroke system). The 3-position gas system allows for normal, suppressed, and bolt-action operating modes. The Modular Railed Receiver (M.R.R.) has a free-floating aluminum handguard and a monolithic top rail system, billet machined 7075-T6 aircraft aluminum alloy. It has an oversized heat-sink barrel nut and a black anodized charging handle. This upper has a 7.62 51mm NATO/308 Winchester chamber. It is compatible with POF-USA P308 lowers only.
|Type||Complete Piston Operated|
|Caliber||308 Winchester/7.62 NATO|
|Sights||None, Optic Ready|
|Barrel Material||4150 Chrome Moly Vanadium Steel|
|Barrel Finish||Black Nitride|
|Receiver Description||7075-T6 Aluminum M4|