S&W M&P15 PS and PSX (piston AR-15)

This year Smith & Wesson have launched the M&P15 PS and PSX piston operated AR-15 rifles.

 Wcsstore Smwesson Upload Images Firearms 811023 Large

The only difference between the PSX and PS is that the PSX features a Troy 7″ modular quad rail handguard.

 Sw Mp15 01-1
M&P15 PS model and Piston Operating System
Remigiusz Wilk (REMOV). Used with permission.


Barrel Length: 16″
Barrel Twist: 1 in 9″
Overall Length: 35″ Extended/32″ Collapsed
Stock: Collapsible 6-position
Weight: 6.5 lbs.
Finish: Hard Coat Black Anodized

I do not know the MSRP on either model.

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.


  • tom sundermeier

    What kind of piston system is it? Is it S&W’s own design, or are they just using some else’s?

    • tom, I wondered that myself. I don’t know.

  • Moe

    It looks allot like my adams arms system.
    I have one of the early ones and have about 6k rounds through it with no hick ups.

  • Sean Nack

    it looks to me like the hk-ish (i don’t know to whom to properly address the credit, but it looks like the system they have on the 416) gas tappet system. i would explain it, but A) i don’t clearly remember how it works and i don’t want to be corrected to death, and B) techincal jargon is definitely not my gig (example: i’m pretty sure the short whosit directs the gas onto the long piston-y thingy, which then contacts an open port on the bcg, cycling the weapon.)

    further: i hope this thing sells like mad, and not only out-sells but embarrasses hk. and that’s coming from a long time hk fan/apologist who is, finally, fed up. good thing they make good handguns.

  • My bet is Adams Arms: http://www.adamsarms.net
    Looks identical to mine.

  • MAJ Tony

    It IS a modified Adams Arms design. I talked to them at the SHOT Show, and Adams supplied the original design with a few mods: “skis” on the back of the bolt carrier to prevent or reduce the propensity of the bolt carrier to wear out the buffer tube, a unitary bolt carrier (no bolted-on key where the rod impacts) and the block will be pinned on. The S&W rep said that the pinning of the block is more of a sales issue than a real mechanical upgrade.

    • MAJ, thats for the info.When you say a sales issue do you mean they just want to differentiate themselves from the standard adams pistol system?

  • Stevegunq

    I just purchased a S & W AR 15 Full rails end to end 16″ barrel and collapsable stock. Ive been wondering about all of the talk between which is better, the new piston or the old gas tube, any thoughts? —-Oh I also put an EOTech on top with a 5x magnifier and harris type bipod, still havent taken it to the range yet am getting grins just looking at it so far.

  • Josh Thom

    The S&W M&P15 PS and the M&P15 PSX use the Adams Arms gas piston design under licence, but the pistons are made by S&W. You can learn more about the piston at the following link.

  • Bobby

    I would buy this if it came in 6.8×43.

  • Lance

    I’ll bet this will be S&Ws rifle in the Army carbine study next October.

  • Bobby

    Is it compatable with a 6.8 bolt?

  • fred t

    the maj. is zeroing in. early 60s amalite introed ar18 into the sys. simaler gas push rod,but after patents changed hands the military & colt went with the standard gas sys. as we know it.

  • MAJ Tony

    To answer Steve’s question, it’s not about differentiation as far as pinning the block. They just believe the perception that pinned blocks are less likely to loosen is worth the $ in the target customer’s eyes. Because of that, even though they don’t think it is necessary from a reliability standpoint, they’re going to do it anyway.

  • Bones

    Is there a .22 conversion for this gun?

  • Moe

    Spikes Tactical has a conversion kit for the .22.

  • Bones

    Ok thanks. Is that the only company that does?

  • MAJ Tony

    Assuming that the S&W use standard BCGs like everything else, any standard blowback operated AR 22LR conversion SHOULD work, as I understand it. We’ve had 22LR conversion units for years. I used one in ROTC in the 90s in college.

  • MAJ Tony

    Note that you will probably have to remove the op rod if you’re using a 22LR conversion unit, as I’m guessing it would strike the conversion unit during firing, or even not allow it to be installed. It comes out thru the gas block, and you can replace the gas plug assy and put it in the closed position when you’re using the 22LR conversion, and replace the op rod thru the gas block when done. At the very least you’ll need to put the gas plug assy in the off position to prevent the op rod from striking the conversion unit.

  • Gary Flynn

    I just bought a Model M&P15OR Rifle .223 do you think S&W will sell a conversion kit, from gas to piston?

  • Talldog

    I wasn’t having any luck finding this rifle at my local gun shops, so I called S&W direct. Apparently this won’t be available for sale until the end of November 2009.

    • Talldog, thanks for the info.

  • Talldog

    No problem Steve, this looks like a nice rifle and has got some good reviews. I just wonder what the MSRP is going to be?

    • Talldog, it will be interesting to see what the price is.

  • racine

    I hope they make this reasonable in price or comparable to the regular AR 15 so they sell a ton of them and blow HK out. Making them in 6.8 would be very attractive as well.

  • Talldog

    Anyone have any news on availability or pricing yet?

  • cory

    The MSRP price for SKU: 811023 is $1,692.00 Thats the piston PSX AR Rifle. I know this because I am about to buy one using the military discount from Smith and Wesson which is 40% until 31 Dec 2009. If there are any retired military or active duty components out there look up this deal, or email me for more info at deadlystrategy [at] yahoo [dot] com I’ll get you hooked up. don’t email me unless your actually military or your wasting your time because you have to show a copy of your ID.

  • LMT makes this rifle in 6.8 full tacticle form for 1995.00.

  • This is the Adams Arms system, it is manufactured in the S&W factory using Adams Arms blueprints and techniques.

    I have a S&W 5.45×39 retrofitted with a REV2 Adams Arms Piston Kit. I have a total of 4 Adams Arms Rifles, 2 of which are SBRs, I have 20K through all of these guns and the only malfunctions I have experienced were caused by ammunition, that being garbage PMC rounds I bought from Jim’s Gunjobbery in Fayetteville NC. I have put Centurion, Wolf, Brown Bear, Priv, Remington, and Hornady through these systems. I have shot handloads too. They all function flawlessly.
    I am also in possession of GB-001A, Adams Arms first production system, so technically I am their first customer. Jason and Jim are the Best!

  • KJ

    You shouldn’t have to remove the drive rod when using a .22lr conversion. The gas setting can be turned off on the 3 o’clock position.

  • Bill

    I sent a message to Adams Arms concerning use of the CMMG .22 conversion assembly and received this reply from John in their sales and marketing group:

    “Yes you can use the CMMG 22 conversion on that AR. Simply remove the drive rod and turn the gas plug to the 3 o’clock or off position. Then follow
    CMMG’s instructions. If you have any other questions feel free to call or
    email and we’ll help anyway we can.”

  • cory

    Got my PSX rifle from S&W Very nice! Thanks S&W

  • 3fingas

    I got my M&P 15 PSX rifle several months ago. All things considered, it’s a fantastic rifle. I had a couple of problems initially with the rifle (bolt-related) in which S&W fixed and returned my rifle within 10 days. They have great customer service.

    Since I got my rifle back from S&W, it has performed flawlessly with all sorts of ammo. To save money, I have been using Hornady TAP Training ammo (Steel cases provided by Wolf?/primer, powder, and bullet from the good ole USA). Regardless, this rifle feeds and shoots all ammo accurately (well, as accurately as I can aim).

    I am very pleased with the piston configuration. It makes clean-up a snap and I don’t notice any appreciable difference in recoil as compared to DI AR-15s. After shooting more than 500 rounds, I haven’t noticed any of the infamous “carrier tilt” associated with some piston AR-15 variants.

    My biggest complaint about this weapon has nothing to do with its piston design. It is trigger pull. The rifle has a very heavy trigger pull (estimate ~9 lbs.). I will probably replace the trigger at sometime.

    I posted a review of my weapon on another site. It has pictures of the rifle and target photos. The review contains all info good and bad.


    I think you can acquire the PSX model for around $1300. This model is competitively priced for a quality piston AR 15. Remember to include at least another $180 or so for quality BUIS (Troy, Midwest Industries, etc) in your cost calculations. Being valued minded (cheap), I picked up a UTG rear and a Magpul front sight. This combination is not ideal, but is adequate enough until I can get better sights. The gas block rail is on the same plane as the upper receiver rail, so make sure that you pick up iron front and rear sights which are designed for the same plane otherwise your sights will not line up properly.

    In conclusion, I am happy with my purchase. The more I shoot it, the more I like it and gain confidence in this rifle.

  • Richy

    Are the S&W M&P 15 PS Handguards interchangeable with other handguards? I’m looking to put on a quad-rail. Any suggestions?

  • Mike

    I have a set of the factory PSX quad rails (made by Troy, marked Smith & Wesson M&P) that are a drop in install on your PS that I don’t use anymore. If you’re interested, shoot me an email (basshead87@aol.com) and I’ll shoot you a price. FYI–S&W is charging $140 for them!

    • Charles

      Mike, I would like the PSX quad rails (made by Troy, marked Smith & Wesson M&P) that are a drop in install on your PS. Please give me an idea of price wanted.