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m4 upper

The M4 carbine is a shorter and lighter variant of the M16A2 assault rifle. The M4 is a 5.56×45mm NATO, air-cooled, gas-operated, magazine-fed carbine. It has a 14.5 in (370 mm) barrel and a telescoping stock.
The M4 carbine is extensively used by the United States Armed Forces and is largely replacing the M16 rifle in United States Army and United States Marine Corps combat units as the primary infantry weapon and service rifle.
The M4 is also capable of mounting the M203 and M320 grenade launchers. The distinctive step in its barrel is for mounting the M203 with the standard hardware. The M4 has semi-automatic and three-round burst firing modes (like the M16A2 and M16A4), while the M4A1 has semi-automatic and fully automatic firing modes (like the M16A1 and M16A3).

View More On Wikipedia.org
Recent contents
  1. T

    Genuine Colt Factory OEM M4 AR15 Upper Receiver Cage Code Marked 13629 Square BAFE Near Mint

      1. For Sale
    • $400
    • Portland
    • Oregon
    Hello, I have for sale two near mint condition Colt Factory OEM M4 AR15 Upper Receivers. Colt Cage Code Marked 13629 BAFE Square Forge Mark. Machined with M4 Feed Ramps and laser engraved T-marks on the Picatinny rail. A thoroughbred upper receiver perfect for a new duty gun or clone build...
  2. huntpotter

    M4 Upper 14.5 P&W Complete 5.56 AR Upper Chrome Bore

      1. For Sale
    • $380
    • Vancouver Ridgefield
    • Washington
    Up for sale, Southwest Washington, Vancouver area, Clark County area. M4 clone upper. Complete with BCG and CH. Bushmaster factory flat top upper. 14.5" Chrome lined 1-9 barrel. With pin and weld extended length A2 flash hider to make it 16.1" total length. 5.56 NATO. Colt M4 double heat shield...
  3. huntpotter

    M4 Upper 14.5 P&W Complete 5.56 AR Upper

      1. For Sale
    • $400
    • Vancouver Ridgefield
    • Washington
    Up for sale, Southwest Washington, Vancouver area, Clark County area. M4 clone upper. Complete with BCG and CH. Bushmaster factory flat top upper. 14.5" Chrome lined 1-9 barrel. With pin and weld extended length A2 flash hider to make it 16.1" total length. 5.56 NATO. Colt M4 double heat shield...
  4. TheRealMP

    Vintage Colt M4 Upper

      1. For Sale
      2. For Trade
    • $600
    • Post Falls
    • Idaho
    Colt Upper with Colt BCG. 1/9 twist HBAR barrel.
  5. Aero Denezol

    M4 Upper w/ BCG & CH PSA 16" bbl Midwest FSP Rail + Matech * Free Ship

      1. For Sale
    • $550
    • Salem
    • Oregon
    Complete M4 Upper w/ BCG & CH 5.56x45 "Block II Inspired". Assembled new, unused. I am the original owner. Includes the following parts: Streamlight Protac HLX w/ 2 tailcap options Midwest Industries Free-Float Extended Carbine Rail Surefire 3-prong Warcomp w/ tool PSA Carbine Length...
  6. MrMykonos

    PRICE DROP Colt M4 Upper w Carry Handle

      1. For Sale
    • $480
    • Pasco
    • Washington
    Keyhole Upper w 16" 1/7 twist barrel also comes with C stamped BCG and original CH. Square forge marked removable carry handle. Asking $525 shipped.
  7. RuckusReckus

    FN M4 Patrol Carbine upper 16

      1. For Trade
    • Portland
    • Oregon
    FN 16" M4 Patrol Carbine 1:7, F-stamped. Got it recently in trade, and like it, but I'm trying to diversify. Some handling marks, shown in photos. ~5-6 mags through it. Wanting to trade for either a 16" dissipator upper, or a 20" A2/A4 upper, maybe NM? Must be 1:7. Totally open to offers as well.
  8. RyanG90

    Looking for stripped M4 upper

      1. Want to Buy
    • Vancouver
    • Washington
    Preferably aero precision, but will consider others. Cash in hand. FTF in Vancouver. Please pm me.
  9. BlackTemplar

    Cerro Keyhole Forged Ghost M4 Upper

      1. For Sale
    • $50
    • Salem
    • Oregon
    Was going to use on a URGI build but moving across the country and extras have to go. Will meet in West Salem or ship flat rate. Need gone by Monday or will ship once I get to Alabama.
  10. BlackTemplar

    Cerro Keyhole Forged Ghost M4 Upper

      1. For Sale
    • $50
    • Salem
    • Oregon
    Was going to use on a URGI build but moving across the country and extras have to go. Will meet in West Salem or ship flat rate. Need gone by Monday or will ship once I get to Alabama.
  11. J

    Colt 6920 M4 Upper and 12.625" Apex GatorGrip Hanguard

      1. For Sale
    • $500
    • REDMOND
    • Oregon
    Like new and has never been fired Colt 6920 M4 upper receiver w/ 16" chrome lined barrel, 1:7' twist with pinned low profile gas block. This came off a Colt 6920-OEM2 and is Colt factory assembled. The receiver has the square forge marking along with the #13629. I never completed this project...
  12. wsu 5.9er

    Aero Precision COP M4 upper receiver, NIB, cerakoted Burnt Bronze

      1. For Sale
    • $700
    • Auburn
    • Washington
    Aero Precision COP M4. Continuous Optics Platform mid-length, has a full-length top rail that is all one piece. Side and bottom rails bolt on. All brand new, never assembled. Comes with factory box, tool bag roll, barrel nut wrench, screwdriver, etc. This is an equivalent length to a standard...
  13. MrSteez

    Standard ar15 m4 upper and aero lower

      1. For Sale
      2. For Trade
    • $600
    • spokane
    • Washington
    I have both halves of an ar15 in 5.56 as marked on 16" barrel. No branding evident on the upper, railed gas block, MPI BCG, no branding either. Like new. Has ruger polymer front sight and carry handle but the sights dont line up. i think you need either a spacer for the front or a fixed iron...
  14. M

    Mueller M4 upper receiver

      1. For Sale
    • $75
    • Everett
    • Washington
    Has forward assist and port door. Picked this up used but in good condition, very minor wear. T marks, no dog bone or m4 mark. $75 shipped. PayPal / Zelle preferred. Can post photos later.
  15. JustAndNguyen

    16" Midwest Industries 5.56 M4 upper w/ Streamlight HLX w/ laser and Magpul RVG and ladder rail panels

      1. For Sale
    • $500
    • Clackamas
    • Oregon
    Hey folks, looking to part ways with this upper MI Basic M4 Complete Upper, MCTAR-17G2 Drop-In Handguard Streamlight HLX w/ laser Midwest Industries Combat Rifle Rear Flip Sight PSA BCG Magpul FDE ladder rail panels Magpul FDE Rail Vertical Grip The PSA BCG has not been live fired, just...
  16. JD42

    New Aero M4 upper

      1. For Sale
    • $70
    • Salem
    • Oregon
    I have a new Aero M4 upper with port door and forward assist. Shipped $70 PayPal gift
  17. RobMa

    - SOLD - New Bravo Company M4 upper receiver with dust cover and forward assist - SOLD -

      1. For Sale
    • $129
    • Seattle
    • Washington
    Sorry, this item has sold New Bravo Company M4 upper receiver. Comes with dust cover and forward assist. Please PM me for any questions I take PayPal friends and family and Venmo Shipping OK, S/H free No trade requests please. No separate part sales please No face-to-face sales requests...
  18. T

    V SEVEN M4 UPPER RECEIVER

      1. For Sale
    • $115
    • Portland
    • Oregon
    Brand new V Seven M4 upper receiver. Never used and comes with original box. I’m pricing it way below what I paid for it and won’t go any lower. Won’t find it cheaper than this. Paid……………$175 Selling………….$115
  19. T

    V SEVEN M4 UPPER RECEIVER

      1. For Sale
    • $135
    • Portland
    • Oregon
    Brand new V-Seven M4 stripped receiver for sale. Never used and in perfect condition. Comes with original box. Don’t worry your lady won’t be upset with ya if ya buy it. She’s cool with it. Online pricing…… $160 - $175 Asking………$135
  20. hungfarlow82

    Colt cage code upper

      1. For Sale
    • $165
    • Happy Valley
    • Oregon
    Used colt upper with cage code. $165 shipped
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