With its polymer receivers, the .22 LR Smith & Wesson M&P 15-22 Sport is a particularly quiet rifle when suppressed. When integrally-suppressed from Innovative Arms? Fuggedaboutit! Adding only four ounces to the weight of the standard 15-22, Innovative Arms’ M&P 15-22 Integral is easily one of the quietest firearms on the market . . .
An aluminum shroud is permanently attached over the ~10″ barrel, extending the effective legal “barrel” length to 16.25″. So, it’s a single-stamp gun (it is not an SBR; it only requires the silencer registration). Some of the reason it’s so quiet is that there’s a lot of volume (as in space, not noise) inside of that tube, which provides the gunshot gases plenty of opportunity to expand and cool down.
Somewhere after the chamber but before the muzzle, the barrel is ported. This bleeds off gas and pressure in order to drop high-velocity ammo (read: the affordable bulk-box stuff) down to subsonic speeds.
And it seems to be just barely enough. CCI Mini-Mags averaged 1,108 fps, which is about 80 fps slower than I’d expect from a 10″ barrel and is 22 fps slower than the speed of sound at 72 degrees F air temp. Of course if it were 34 degrees out, every round I sent over the MagnetoSpeed chronograph would have been accompanied by a sonic boom.
American Eagle Suppressor .22 LR runs 970 fps out of a 16″ barrel, but I don’t know what to expect from it through a 10″ barrel (ported or otherwise). At any rate, it averaged 855 fps through Innovative Arms’ M&P 15-22 Integral. Note that single-digit standard deviation, by the way. I really love this ammo.
Though the Integral comes with a take-down tool, the end cap will accept a normal 3/8″ socket wrench.
Lefty loosey and the core begins backing out of the tube. It’s threaded into the end of the tube rather than onto the barrel. As you spin the core, its snug fit scrapes carbon and other combustion byproduct off the walls of the tube.
The 6-inch, stainless steel, monocore baffle pulls out the rest of the way by hand, ready to be dropped into an ultrasonic tank for cleaning or scrubbed down with the brushes and cleaners of your choosing.
Around to the receiver side and we find the standard S&W M&P 15-22 bolt, recoil spring, and charging handle setup. Really, if I could change one thing about this gun right off the bat it would probably be swapping out the plastic charging handle for an aluminum one. I don’t mind the polymer receivers at all and, while the polymer charging handle is sufficient, it just feels flimsy.
It’s all standard M&P 15-22 inside of the lower, too. Which isn’t a complaint. The trigger’s actually better than a normal AR-15 “mil-spec” job. The 25-round magazines are great.
And it runs. It runs and runs and runs. I borrowed this rifle from Silencer Shop (priced under a grand there) and it has apparently been through the ringer. Something like 10,000 rounds during demo days and company picnics and loans to bloggers. It certainly looked well-used, with green copper patina scale on the barrel around the chamber and that sort of baked-on, crackly carbon layer that takes dedication to build up and age like a fine wine. Or cheese crust.
Anyway, I upped the round count more than necessary and had only a single stoppage due to a primer-less round. It cycled subsonic ammo like the aforementioned American Eagle Suppressor stuff and a few brands of match-grade ammo without a hitch, and it cycled what would normally be supersonic stuff like Federal Hunter Match, Mini-Mags, and a couple bulk brands as well.
Through all of this, zero blowback detectable on my face or hands. While not often a big issue with a suppressed .22 LR rifle anyway, it was still notable in its complete absence even during magazine dumps. The ported barrel and large amount of space inside of the suppressor tube likely lead to particularly low backpressure.
At 25 yards off a sandbag with a red dot, accuracy was okay. Norma Match-22 turned in the tightest, 5-shot groups of about 0.68″. Mini-Mags netted 1.06″ and the AmEag Suppressor about 1.14″.
Not match-grade, but that’s not what it was built for. Of course, 10,000 rounds ago it may have fared slightly better. I did run a bore snake through it a few times to ensure it was at least chunk-free.
The Innovative Arms M&P 15-22 Integral is extremely quiet, which is what it was built for. From the shooter’s perspective, it seems like the action cycling is responsible for most of the noise. A bit of speculation on my part here, but if this gun were built on aluminum receivers I think it would be noticeably louder. The actual shooting part is so darn quiet, it’s all about the action.
In Silencer Shop’s testing, this thing meters at like 113 dB. That’s about as quiet as any suppressed .22 LR gets. I actually wish the M&P 15-22 had a forward assist so I could hold the bolt shut and meter it with and without the action’s action.
Numbers aside, though, when shooting this gun outside it’s quieter than a paintball gun, quieter than many BB/pellet guns, and quieter than the spring-powered staple gun we had on hand. Well, okay, quieter than the staple gun when stapling targets on wood; approximately a wash when just firing staples downrange. Perhaps the only quieter gun is a caulk gun. Or a glue gun. It’s way quieter than a tape gun.
The extra four ounces is hard to notice, but may even be a positive. A little extra weight at the muzzle helps the rifle handle a bit more like the real thing, swinging between targets and shouldering less like a toy and more like something with a bit of gravitas. With an empty mag and the stock collapsed, the center of balance is at the pivot pin. It handles nimbly and feels neutral.
This setup — sold as a complete rifle — comes highly recommended. It’s light, nimble, reliable, holds 25+1 rounds, and is a hoot to shoot. Oh, and it’s quiet. Like basement shooting gallery (where legal) quiet. Like backyard pest control (where legal) without waking the sleeping cat quiet. Like dropping the bolt on an empty chamber is louder than firing this thing and chambering the next round quiet. It’s silly quiet.
Specifications: Innovative Arms M&P 15-22 Integral
Caliber: .22 LR
Suppressor Build: Aluminum tube, Type 3 hard coat anodized, and 17-4 PH stainless steel baffle core
Capacity: 25 rounds
Action: Straight blowback
Length: 33.8″
Weight: 5.05 lbs
Barrel: 10″ ported barrel with permanently-attached aluminum suppressor tube for 16.25″ effective legal length
Receivers: Polymer
Furniture: 10″ polymer M-LOK handguard, Magpul sights, parts kit style pistol grip and stock
MSRP: $1,150 (about $200 less via Silencer Shop)
Ratings (out of five stars):
Accuracy: * * *
Nothing to brag about, but it’ll do the trick for keeping raccoons, skunks, possums, and aluminum cans at bay. In fact, with the iron sights I was consistently hitting a 1/2 IPSC-sized steel silhouette offhand at 100 yards with Mini-Mags, and I think most misses were due to wind.
Ergonomics: * * * *
Ultimately, it’s an AR-15. A lightweight one at that. It would be five stars with a better pistol grip, charging handle, and maybe a nicer stock. All easily upgraded, of course.
Reliability: * * * * *
Not a hitch. Appears to be reliable and durable, too.
Customize This: * * * *
The M&P 15-22’s AR-15 parts compatibility, limited though it is, opens the door to tinkering, swapping, and upgrading many of its components.
Overall: * * * *
Holy Hannah is this rifle quiet. It’s also handy and reliable. If it shot those groups at 50+ yards instead of at 25, I’d be hard-pressed not to give it five stars. Though that plastic charging handle still has to go.