Sig M400 AR-15 5.56/223 Carbine 16" Barrel 30 Rd mag

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Manufacturer Number:
223 Remington
Sig Sauer M400
Unit of Measure:
SIG M400 SRP 5.56 NATO 16" 30RD TELESCOPING STOCK FLIP-UP REAR SIGHT, "F" MARKED FRONT SIGHT, 6-POSITION TELESCOPING STOCK, SIG SAUER GRIP, NITRIDE TREATED BARREL, AMBIDEXTROUS CONTROLS DIRECT IMPINGEMENT GAS OPERATING SYSTEM WITH ROTATING LOCKING BOLT, A2 TYPE FLASH SUPRESSOR, ACCEPTS MOST AR15 TYPE MAGAZINES No, all M4 are not alike. The Sig Sauer M400 has out of the box ready performance, more features, and no gimmicks, for when it really counts. Featuring chrome lined barrel, M4 contour barrel with 1:7 twist, removable carry handle and sight, ambidextrous mag release, quick detach sling mounts integral to receiver, supported extractor, and Accu-Tensioner.
  • Category : Tactical Rifles
  • Action : Semi-Automatic
  • Caliber : 223 Remington/5.56 NATO
  • Barrel Length : 16.0"
  • Capacity : 30+1
  • Trigger : Standard
  • Safety : Lever
  • OAL : 35.6"
  • Weight : 6.5 lbs
  • Stock Description : 6-Position Black
  • Metal Finish : Black
  • 5
    M400 is worth the $$$

    Posted by flashbang66 on May 21st 2012

    I've had the m400 for about a month now, and it's a beautiful rifle! Solidly built, sturdy construction, definitely a joy to handle. The only "wiggle" I can feel is from the Magpul stock I added (the upper and lower hold tight!). Many comments on the Internet say that it's too new to trust or overpriced, but after a 1000 rnds with no FTF or FTE using Lake City M855 ammo, all I can say is wow! I consistently get groups of 1.5" - 2" at 100 yards on iron sights. Beware of reviews saying that it has a com-spec buffer tube, it's mil-spec. Also, it will not accept the Magpul ambidextrous sling adapter because of the QD knobs at the rear of the lower receiver (I had to go with a Tapco). Enjoy!

  • 5
    M-400 Excellent

    Posted by GROG on Mar 27th 2012

    Just took my new Sig Sauer M-400 out to the farm. With the exception of the mag it worked flawlessly, very nice. About 400 rounds through the gun after I changed the mag to D&H 5.56 30rd AR15 Magazine Black Teflon. The mag on the other hand is crap when I called (SIG) to complain their justification for the mag was, well this is the same mag that is issued to the troops. Something is very wrong with this picture.

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