Knight’s Armament SR-15 IWS E3 Carbine Mod 2

KAC carbine

Knight’s Armament (KAC) is now making a second version of the company’s SR-15 IWS carbine.  According to KAC, the Mod 2 has a number of new features including:

  • a URX4 hand guard with Keymod accessory mounting points.  KAC states the URX4 keeps the barrel cooler and reduces the gun’s overall weight when compared to other rail systems.
  • a proprietary Mod 2 gas system that minimizes leakage and ensures more consistent operation in harsh conditions.
  • a gas block secured with a locking ring instead of taper pins to increase barrel rigidity and eliminate the need to custom fit the gas block to the barrel.

The rifle is also designed to be ambidextrous, with magazine and bolt releases on both sides of the receiver.

KAC carbine


  • caliber: 5.56 NATO
  • barrel:  hammer forged, chrome lined
  • barrel length:  16″ with a 1:7 twist
  • gas system:  mid length
  • trigger:  two-stage match
  • stock:  six-position SOPMOD buttstock
  • sights:  folding sights included, 200-600 meters
  • unloaded weight:  6.6 pounds

Thanks to Henry for the tip.

Richard Johnson

An advocate of gun proliferation zones, Richard is a long time shooter, former cop and internet entrepreneur. Among the many places he calls home is


  • Vitor

    KA really makes some beautiful ARs and always nice how they tweak the DI system and BCG to make it reliable as possible without a piston.

  • Quach

    Was going to get a MOD 1 but glad I waited. This will be my high end AR to get.

  • clinton notestine

    looks very G3 at the front

  • Chris

    My God. I know you gotta write about them, but… it seems like half of the stuff on this blog is a new type of AR that some other company is making that looks like every other AR. AR AR AR AR AR AR AR AR AR

    • TheSmellofNapalm

      This is not your average rifle, and if you think it is please do a little research.

      • Nicks87

        Oh, give me a break, just because it’s KAC doesnt make it something special. You are just paying for the name. Please tell me what makes this rifle better than a Noveske, BCM, LMT, Colt, Etc. There are plenty of companies out there that can build the same quality rifle at the same or lower price.

        • TheSmellofNapalm

          Oh I don’t know, let me think…

          -E3 bolt
          -Enhanced gas system
          -Muzzle device accepts QDS
          -Flawless service reputation

          Finally, a company that ironically debuted the platform dares to go non-milspec to improve performance.

          • Nicks87

            Ok, so that stuff makes it a better rifle than the ones I listed? How?
            Yet again you are buying into KAC’s marketing ploy. I’m not really sure how non-milspec is an improvement. Round bolt lugs, smaller gas port, no thanks. Proprietary parts mean you have to buy new ones from KAC and the ones in-stock at the local gun shop wont work. Might as well just buy a piston AR and get more for your money.

          • TheSmellofNapalm

            Cool man, you can stick with your mediocre “gets the job done” rifle, and we’ll all go get what has already proven to be a superior platform. I feel sad for your gun safe

          • John

            Yes, we’ll all go out and get AKs, the only “proven” “superior platform”.

            Seriously, this is just a very very pretty AR for Kool-aid drinkers and I must admit I own more than my share of those too (JP 9mm, MR556, LMT MRP, Colt Socom II, Seekins + Mega Side Charge, etc, etc). Deep down inside we all know an overgassed Delton or DPMS is just as good. Still, I will probably buy this once KAC stops changing the rails every 6 months when it’s URX8 and Mod 6.

          • Nicks87

            Superior to what? Bushmaster? DPMS? The list goes on and on and on. Maybe 10-15 years ago KAC was top of the line but the industry has caught up and surpassed them in some areas. The point is: There are so many companies making good ARs nowdays that to say one is better than another is just asinine.

            I think I will stick to building my own match rifles. Chrome lined barrels just dont deliver the accuracy I require. They are more for the “gets the job done” crowd.

    • Guest

      Clearly, you don’t know what you’re looking at here.

      • Nicks87

        Yep, you dont see one of these everyday, what an exceptionally rare rifle!!! (sarcasm, if you couldnt tell)

    • Creep

      Well, it’s a popular product. Of course a new design/feature/accessory is going to be mentioned.

    • Micki Mahoney

      TFB: “We got more ARs than a stuttering pirate.” :p

    • Cymond

      It seems that there is at least one comment on every post about modern rifles, and it falls into one of 2 categories:
      If AR-15: “OMG, yet another AR-15, just like very other AR-15.”
      If not AR: “It doesn’t do anything better than an AR-15.”

  • Mark

    6.6 pounds with all that rail. Not bad. Your run of the mill AR with all MOE polymer is 6.9-7lbs.

    The previous SR-15 rifles were actually a good deal @$1800 considering the components when you could get them for that. I’m sure this will be well North of $2k.

  • Will

    Does anyone know when KAC will be shipping these? Or when they will be available in stores?

    • Aric

      I have heard early May. Hopefully mine will show up then.

  • jared

    I’d rather be behind Knights Armaments 6.35 PDW. It’s armor piercing round and reliability it’s flawlessl. Not to mention it’s short stroke piston allowing the round to be chambed smoothly and rapidly…. I’d feel quite at home with this weapon.

    • TheSmellofNapalm

      Yeah, cuz screw parts and ammunition compatibility