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Sons of Liberty Gun Works

M4 Patrol Upper Free Floating ERGO Z Rail CS01

$ 549.00
or

Need more details? Call us at (210) 400-5992

M4 Patrol Rifle

This upper very closely resembles the Military issue M4 but with an Free Floating ERGO Z Rail. Everything you need in a patrol rifle and nothing you don't.  Our only rifle to come with a vertical grip standard, it is ready to go right out of the case.

Sons of Liberty Gun Works we believe in Quality Mil-Spec or better parts. We believe there is no substitute for quality and that your gun should be built right the first time, ready for hard use right out of the box. We believe a quality Bolt Carrier Group and a quality, accurate and long lasting barrel are the heart of a Combat Grade weapon. We believe in properly tuned weapons using the correct gas system length and quality buffer system components such as Sprinco Tactical Buffer Springs. We believe in our products and we back them up with a Lifetime Warranty. Our weapons our meant to be used hard and go in harm’s way, they won’t let you down.

All rifles are test fired twice in shop to ensure proper function

Bolt Carrier Group: Sons of Liberty Gun Works Bolt Carrier Group HPT/MPI
Bolt: precision machined from Carpenter Technology No. 158 alloy, heat treated per mil-spec, shot peened per ASTM B851/SAE AMS2430S, vibratory tumbled, individual high pressure/proof test fired (HPT), individual magnetic particle inspection ASTM E1444/E1444M (MPI), markings deep laser engraved (SP=Shot Peened/HPT=High Pressure Tested, MPI=Magnetic Particle Inspection.
Extractor: precision machined from 4340 tool steel alloy per SAE AMS6415T/AMS6484D (vs typical 4140; mil-spec allows for either 4140 or 4340), heat treat, shot peen per ASTM B851/SAE AMS2430S.
Extractor Retaining Pin: precision machined and ground S7 Tool Steel, heat treated per ASTM A681-08, shot peened per mil-spec print, manganese phosphate
Extractor Spring (premium spring eliminates need for Crane O-Ring), Tactical Springs/Sprinco 5 coil, ASTM Grade A401 Chrome Silicon wire stock, heat treated, stress relieved, Molybdenum-Disulfide infused, cryogenic processed (all post winding), mil-spec black insert/synthetic elastomer extractor buffer (nitrile-butadiene, shore hardness 80+/-5 durometer per MIL-PRF-6855)
Ejector: S7 Tool Steel, heat treated per ASTM A681-08, shot peened per mil-spec print, manganese phosphate
Ejector Spring: heat treated, stress relieved, Molybdenum-Disulfide infused, cryogenic processed (all post winding)
Gas Rings: mil standard stainless steel X3
Carrier: machined from AISI 8620 aircraft qualty alloy per ASTM A108/A322-13, full auto profile, heat treated (carburized/strain relieved per mil-spec print), hard chrome bore, precision ground gas key interface, Sons of Liberty Battle Flag logo deep laser engraved, manganese phosphate
Gas Key: machined from 4130 chromoly steel alloy per ASTM A108/A322-13, heat treated, hard chrome internal, manganese phosphate, Permatex sealed, Grade 8 Torx Plus cap screws torqued and staked all per mil-spec
Cam Pin: precision machined 4340 chromoly steel alloy per SAE AMS6415T/AMS6484D, heat treated/processed per mil-spec, manganese phosphate, solid film lubricant applied and cured per mil-spec
Firing Pin: precision machined 8640 steel alloy, heat treated/processed per mil-spec, hard chrome plate
Firing Pin Retaining Pin: precision machined from 1038 carbon steel, heat treated/processed per mil-spec, manganese phosphate

Barrel: Sons of Liberty Gun Works 16” 4150CoMOV 1:7 MPI HPT Barrel
Caliber: 5.56 NATO Chamber
Barrel Steel: 4150 CrMoV (Chrome Moly Vanadium per MIL-B-11595E)
Twist Rate: 1/7 Twist Six Groove
Thread Pitch: 1/2-28 Threaded Muzzle
Gas Block: .750″ Gas Block Journal with appropriately sized gas port
Weight: 29 Ounces
Barrel Finish: QPQ Corrosion Resistant Finish
Barrel Extension: QPQ coated M4 Feed Ramp Extension
High Pressure (proof) Tested (HPT)
Magnetic Particle Inspected (MPI)
With "F" Marked Taper Pinned Front Sight Block

Upper Receiver:
Material: Made from Mil-Spec 7075-T6 aluminum Cerra Forge forgings.
Exterior Finish: Anodized to Mil-Spec MIL-A-8625F, Type III, Class 2, Hard Anodic Coating, Flat Black Dye, Non-Reflective, NiAc Seal
Interior Finish: Dry Film Lube
T-Marks: Engraved T-Marks

Charging Handle: GI Charging Handle

Gas Block: Sons of Liberty "F" marked Front Sight Block made from 4140 Steel and Nitride Treated

Gas Tube: Sons of Liberty Standard Mid Length Melonited Stainless Steel

Hand Guard: ERGO Carbine Length Free Floating Z Rail

Muzzle Device: Standard A2 Flash Hider

Sights: Rear Magpul MBUS Sight Black
Front: "F" Marked Front Sight Block

Accessories: SOLGW Sticker & Patch, Trident Concepts TACOST card deck, copy of the US Constitution, and LIFETIME Warranty

Sons Of Liberty Gun Works was founded on the principle of producing hard use, purpose built weapons for Americans in 2012. Our company was founded by two lifelong firearms enthusiasts and one US Navy SEAL. We produce a wide range of products including M4 based rifles and Mk10 Rifles, over take on the classic AR-10.  

All our products are backed by a LIFETIME Warranty.  We can do this because we believe in only providing products that we believe in and would stake our reputation on.  Our entire staff has been thoroughly trained by the best armorers in the proper procedures to build and diagnose problems with the M4 platform.  

We provide in house custom rifle builds, repairs, cerakote, special order of non AR Platform firearms, training on the AR platform and consulting work.  Come by and check us out, our doors are always open and the after hours beers are always cold.

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