Gun Review: Knight’s Armament SR-15

[ I am pleased to present this post written by Isaac. ]

Knights Armament as a company has had a notable hand in the evolution
of Eugene Stoner’s classic AR-15 design. One of the most obvious
results of that heritage is visible in the SR-15 E3 IWS (Integral
Weapons System).

The biggest question when people see the SR-15 is “what’s different
about this gun to make it special?” And to answer that is to look
under the hood and understand that the SR-15 doesn’t seek to be the
most accurate, or the most durable gun (the SR-15 E3 IWS actually
groups 1.25moa or better, so it’s no slouch). What it does is be one
of the most complete package rifles that require almost no user
modification or tweaking. And by doing so is an incredibly reliable
and lightweight rifle with a plethora of features.

From the inside out Knights has given the SR-15 a longer than mid-
length gas system, which provides for an extremely smooth and reliable
operation. The rifle also features a larger bolt cross section, which
serves to improve overall durability. The hammer forged barrel groups
very well, and in combination with the very lightweight URXII rail
(including integrated front sight, and included match grade rear
sight), gives the gun an extremely svelte appearance and light overall
weight. All combined with their match grade trigger assembly and
offering completely ambidextrous controls to those who are southpaws
(or shooters working off their reaction sides).

So, SR-15 feature primer aside, how well does it actually shoot?
Amazingly well. Having run the gun in a few carbine courses and
competitions, and run it hard, the gun has easily become the rifle I
count on as my ‘go to’ gun. What it offers me is an extremely
lightweight rifle (even running lights and lasers) that gives me an
above average level of accuracy from a fighting carbine. Short of
changing out some furniture to fit my personal needs, the gun has not
required any tuning or fixes. An extremely smooth gas system in
combination with the Knights Armament triple tap brake (not included)
creates a rifle with almost zero muzzle flip. In the end what the
rifle brings to me is a gun that far exceeds my own capabilities as a

The value of the SR-15 E3 IWS is obviously relative to the needs of
the shooter. Some may never need the features of the SR-15, and that’s
a valid point. However considering what you get as a package (LMT
SOPMOD stock, 16” hammer forged barrel, ambidextrous lower,
lightweight continuous railed forearm, etc) you’re getting a great
value. For those who want or need a gun that requires practically no
modifications to achieve maximum durability and performance, this is
obviously an excellent choice that far exceeds the levels of what make
up a top tier AR-15 rifle.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Dow

    Why is the brake so shiny?

  • Titleist

    It’s one of the earlier generation triple tap brakes, which is made of inconel, and left in the raw. It darkens from use and ends up looking like this, especially in combination with a KAC NT4 QDSS suppressor:

  • jdun1911

    That’s shinny brake cost $450+ and not including shipping. I personally think it is not worth it. A $30 brake does the same thing unless you’re using KAC suppressor.

    14 pages of fanboy discussion on it and counting.

    I like the integrated sling swivel mount on their lower receiver. I’ll bet they have a patent on it.

  • jdun1911

    I mean “That and not That’s”.

    Anyway it cost $435 not including shipping at Operationparts. You have to get it fast tho. Once they have in stock and people post it up on, it usually sold out within a hour or two.

    Here is another fanboy thread on it.

  • jdun1911

    Is that a Magpul ASAP you got there? You decided not to use the integrated QD swivel mount? That’s the best part about KAC lowers.

  • Titleist

    jdun, I do have a KAC suppressor and thus I think it’s worth it. Nuff said, personal preference.

    And yes it’s an ASAP, the KAC QD points are absurdly placed, and do not work well when shifting from weapon to reaction side.

  • jdun1911

    I understand that the KAC QD mount isn’t ambidextrous and will cause some trouble with the reaction side.

    I have a ASAP and I find it is a pain to install. I don’t like the ring attached to the ASAP. I understand the ring was there to allow the stock to be close but I think there is a better way to handle it.

    The Noveske QD end plate is the best tho.

    Anyway great rifle. Put some more rounds through the rifle to turn the brake into black. It looks much better in black.

  • jdun1911

    I mean great carbine and not rifle.

  • Big Daddy

    I by no means am not an expert!!!!!


    All that brake is basically the inside part of a suppressor. In fact it works with the NT-4 KAC suppressor and in fact is considered the first stack. So that’s what it is, the inside part of a suppressor without the can.

    It does get black with use and the material is very hard, so that it prevents scraps from bullets, especially in full auto. From what I have read it does work though. But so do so many others.

    It is really designed to be used with the NT-4 as a system. If you do not have the matching suppressor than you don’t need it and can use one of the many other proven designs.

    KAC…….the company is what it is.

  • Dlw

    Thanks. Great post.
    So between the lower mounted swivel point the asp and perhaps a stock mounted sling swivel what are the pros and cons? Also there are the buffer tube mounts for sling swivels (which seem to be a favorite of pat Roberts 6940s ) that do not seem to locate the sling point that far from the KAC point so what about those?
    Understand the asp is single point so what about just two point systems?