Smith & Wesson M&P 15X 5.56mm

I was surprised a few years back when, on a…

I was surprised a few years back when, on a trip to my licensee’s premises, I found Smith & Wesson had shipped a long gun to me. Opening the polymer container, I found the M&P15T. The “Tango” had a free-floating 16-inch barrel, 1-in-9-inch rate of twist and was chambered for 5.56mm NATO. The sights were flip-up, front and rear, made by Troy.

I took the new rifle out to the police range and the rangemaster had some fun shooting it, as did I. I immediately took to the M&P15 line of AR carbines.

smith_wesson_2.jpgSince then, I’ve been the beneficiary of several trips to Wyoming with S&W and SureFire, among others. The M&P was prominently featured, especially the Performance Center versions with big optics, fairly light and really clean triggers as well as specialty barrels.

Last summer was no exception. S&W brought some other rifles, including the new M&P15X. I’d been told that this was the most popular law enforcement package Smith & Wesson makes and it’s no wonder. A 16-inch, 1-in-9-inch twist carbine, it is provided with a Troy Folding Battle Sight (rear), a four-rail tactical handguard and a 6-position collapsible stock.

This is (almost) the M&P15T at a lower cost. It has everything the agency wants, including optics-ready capability, with nothing it doesn’t need. One of the “x-rays” was made available to me. It was fitted with a Trijicon ACOG (Advanced Combat Optical Gunsight) 4×32. I used that carbine for much of the time I was there. I’d hate to have to estimate the amount of ammo that chugged through that gun, but I believe it to be well in excess of 1500 rounds.

Trigger Details
The trigger on that example was service grade serviceable. It was long, gritty and creepy. I worked to make hits and it was well worth the time. I can tell you, the trigger was much better at week’s end than it had been at the start of the testing.

The Performance Center guns had a trigger best described as a whisper, if you describe the X’s as a stomp. The trigger was something I needed to use. It’s more like the triggers I’ll face if I have to use one of these rifles operationally. In fact, I’d say the lighter, shorter trigger would hamper me operationally. Longer and heavier, as long as I train with it and can control it, is better.

Since the inception of the S&W M&P15 project, I’ve handled no less than 12 different M&P15 samples in numerous variations. I even got to shoot one PC gun chambered in .204 Ruger; that was quite a gun. I’ve been happy with every one I’ve handled. S&W shipped an “x-ray” for me to home base. I wanted to spend some quality time with it.

Gun Details
As the M&P15X was the second M&P in the stable, I reduced the designation to the phonetic of the suffix in the model name. The “Tango” referred to earlier has been around for some time and it would be a good choice for the precision shooter/spotter whether on a response team or a rifle squad. Good magnifying optics properly set for use with a 16-inch 5.56mm and a specific load would be good, along with irons set at 1 o’clock for the sudden, close-range encounter.

The “X” with a reflex sight or with the Trijicon I’ve been using, is a patrol rifle. Effective engagements at 100 to 150 out to 200 yards are eminently doable if you can identify the threat and it’s not moving fast and unpredictably.

I elected to use the Trijicon ACOG TA31TRD 4x32mm optic. I also took the time to attach a vertical foregrip, this one a TangoDown Shorty, just for comfort. Not having yet permanently installed a light, I haven’t installed the forend covers supplied by S&W. I did install a Streamlight Thunder Ranch Urban Rifle Illumination System light, their TL-3.

This sample X was S&W M&P all the way. The prominent markings left no doubt as to the carbine’s origin. The end of the barrel is graced with an A2 flash suppressor. The pistol grip, stock and magazine are GI-ish, as is the front sight tower. The rear sight is by Troy Industries, prominently marked with the S&W logo.

I was a little surprised at the magazine that was packaged with the carbine. It was an aluminum-body, GI in appearance with green follower. I’d heard a rumor that S&W was going to package its M&P15 line with something a little different.

In fact, I’d seen an M&P15 with a Lancer Systems magazine at a recent trade show. The Lancer L5 translucent polymer AR magazine has a body marked with round count at intervals and has hardened steel feed lips that have been treated with PTFE. The floorplate is a rubber-coated bumper; they must assume that empties will hit the ground. The L5 has been tested at high and low temperature extremes.

Another potential alternative magazine is one we’ve been using around here for some time. That’s the MagPul PMAG. PMAG stands for “Polymer MAGazine.” These are AR magazines for the 5.56mm NATO, available with standard bodies or with a window to help you keep track of remaining rounds. A pop-off storage/dust cover keeps the pressure of the stack of rounds off of the feed lips. This prevents the aluminum magazine malady, “ammo creep.” The PMAG features an anti-tilt follower, as one might expect from MagPul, the home of anti-tilt followers for standard magazines, and stainless springs.

Now available in a 20-round edition, the PMAG has a track record of reliability in operations around the globe. My local police response team has been using them, as have I. I’m unquestionably a fan.

Range Time
I made but a single trip with the current sample X to the range. As this sample is destined for suppressor testing later on, I wanted to get some shooting done to check it out before changing anything.

I installed the Trijicon ACOG TA31TRD. This is the 4x32mm ACOG with a TRD (Trijicon Red Dot), placed on top. The little reflex sight is there for room-to-room combat and other close-range encounters of the worst kind.

This ACOG has dual illuminated reticle with tritium supplying light in the darkness and a fiber optic tube providing illumination in better-lit conditions. The reticle is a ranging type with bullet drop compensator. The reflex has an 8-MOA aiming dot.

The TA31TRD is supplied with a flattop mount, a scope coat, a Lenspen, manual, warranty and it’s packaged in a medium Pelican case.

I elected to take the short time I had and try the sample’s accuracy. I used the Lancer L5 magazine as I’d had experience locally with the PMAG with the local response team and with my own magazines.

I tried four different loads for accuracy. Even though it was 38 degrees with winds at 10 to 15 MPH, the range wasn’t empty. I got to use the 50-yard backstop. I braced the X-ray over a range bag. I found the Winchester 55-grain Ballistic Silvertip would put five rounds into 1.06 inches. Hornady 60-grain TAP Urban put the same number of rounds into a 1.13-inch cluster. CorBon 53-grain DPX gave a 1.56-inch group. Black Hills blue box, remanufactured, loaded with the 60-grain V-MAX bullet fired a 0.88 of an inch group at 50 yards.

The X was typical of 16-inch AR carbines and could be expected to display 2- to 4-inch groups at 100 yards. It seems to be what the breed is built for. That said, with the right load and a trigger that slicks up from use, you could get some sub-2-inch groups with this particular gun.

Final Notes
With all the M&P15 versions out there, why does the M&P15X stand out? It’s the format, how the rifle is supplied. It doesn’t need a free-floating barrel for its mission. The railed forend is a help to install the (definitely needed) white light and the vertical grip, which is handy especially if you have to deploy the piece for a long time.

It’s not provided with the removable carry handle. Everyone takes those off and stores or sells them. Imagine having to deploy 100 patrol rifles. Do you want to store 100 carry handles in the armory?

The Troy Industries flip-up rear sight is an industry standard and it’s a good unit. There’s a good reason that the Smith & Wesson M&P15X is so popular with law enforcement, it has everything that’s needed with nothing that isn’t.

Load Comments
  • AJ

    I have the MP 15 Sport and the X. Both have 5.56 on the barrel and have had 100’s of 5.56 nato rounds put down range without a problem. Great guns!

  • Kendall C

    Looking on the S & W website, it does say the round is chambered for 5.56 or .223. I always wonder about that also… Good shooting to you.

  • Shane

    In response to Robert Perry’s question:

    To be honest, I’m quite positive that the M&P 15 (in any version) is chambered in .223 and not 5.56mm. I could be wrong, as I have done many searches and have found no substantial proof to the contrary. I’ve even written S&W to clarify; I didn’t get a response. As I am sure you are aware, there are some substantial differences between the two rounds. A five minute google search will yield several articles explaining those differences in greater detail. To sum this up, it’s not a good idea to shoot 5.56 out of a weapon chambered for .223. In my opinion, it would be best to stick with the .223 until someone can prove the rifle is actually chambered in 5.56mm. Hope this helps… and I hope that someone can shed some light on this, because I am really interested in the 15X, but have been hesitant to buy one simply for this reason.

  • Robert E Perry

    Hi Rich, Thanks for the great article on the M&P15X, I have this Rifle and the M&P15A which I purchased Both the same day on Base at Fort Knox. They have a great selection of Rifles in there Gun dept. I am a Navy Veteran and was stationed at the Amphibious Base Coronado. I was so glad to hear your story and opinion on the X, this is like reassurance of money well spent and that I have at the moment one of the chosen M&P15 to use snd especially that it’s from the Law enforcement side. I have the Green Dot myself, is there a prefrance for you between Red and Green and why? Also do you ever practice with .223 or is it always with 5.56 amunition. To be Honest I’ve only shot .223 in mine, well as you know it’s cheaper but am I harming my Rifle by not using 5.56 you think? Again Thanks and I’m glad I found this site, Robert