Suppressing the legendary 5.56mm rifle round in short barrels is a challenge that silencer manufacturers have attempted to master for decades. Containing a large amount of deflagrating powder as it leaves the muzzle results in extreme heat, pressure and blowback – forcing even the best scientists and engineers to make trade offs. Not to mention the supersonic crack generated when that ~75 grain projectile breaks the sound barrier. In what is being called the quietest 5.56 short barrel setup currently available, silencer industry stalwart Gemtech has designed the Integra – an integrally suppressed AR15 upper receiver group.
Looking at the pictures, ‘short barrel’ and the Integra may seem to be a misnomer. After all, together SBR and AR15 could mean a ~10 inch compact package. But adequately suppressing that shorty usually means adding a brake or flash hider mount, a mounting system and of course the silencer itself. The end result is an SBR with a total suppressed length of 18 to 20 inches. Ouch.
Normally reserved for rimfire and pistol caliber setups, integrally suppressed firearm designs attempt to reduce overall length while boosting overall signature reduction. Although some of these builds include barrel porting to drop muzzle velocities below the speed of sound, Gemtech’s latest release is not ported. Dropping 1500 feet per second (fps) off typical 5.56 velocities would neuter it down to rimfire energy levels.
Instead, the Integra relies upon a large amount of internal volume, a proven monocore baffle design and a unique gas management system to provide the shooter with a a very quiet, nearly gas free trigger-pulling experience. How quiet? Very – but let’s not get ahead of ourselves.
I like to start every review with a couple of quick thoughts. First, I am not an AR15 god. I have not worn out barrels or piled up brass high enough to make a metal recyclers proud. Along those same lines, I am not the silencer equivalent of the “all seeing eye” with an encyclopedia’s worth of knowledge and experience. However, I can give you a real-world review of the design, performance and features of certain suppressors to hopefully give you a better idea on how a particular product would fit into your arsenal.
Lastly, it is your responsibility to follow all firearms laws and regulations as well as all the safety rules. If you need to ask what those are, put the guns back into your safe until you know and understand all of them.
It is a rare event for me to have access to a pristine silencer and AR15 upper combination for a few weeks of review. That’s right, this Integra is factory-fresh, direct from Silencer Shop’s library. So, as painful as it was to hold off jamming mags and pulling triggers, I first took the Integra inside for a basic breakdown and to read the included documentation.
My first task was to get a look at the G-Core monocore baffle stack. Gemtech has thoughtfully made the bore of the core a 3/8″ square, meaning that any 3/8″ socket wrench or socket adapter can be used to remove the core from the Integra’s barrel and tube. The instructions call for using an an action block or a reaction rod, but I was able to loosen the core by placing the upper between my legs and applying an estimated 25-30 foot pounds of torque. (No jokes please, this is a professional publication).
One of the more interesting attributes of the muzzle face of the monocore are the four holes that are open to the inside of the silencer. Obviously, these ports will vent gases forward (more on that in a little while) but they also may aid in water drainage in the event of being submerged. Most likely a rare occurrence for typical civilian shooters, however Gemtech has mentioned that the Integra has been in use by special teams in the United Kingdom for several years. It’s also worth noting that the ports are angled to divert gas in a counter clockwise direction which would apply clockwise (tightening) force on the core. This should prevent the core from loosening under fire. A very smart touch in my opinion.
The build quality of both the Gemtech silencer and the upper receiver group’s components are obvious and appreciated – Gemtech did not cut any corners. from a properly staked gas key to a magnetic particle inspected (MPI) marked bolt, these are top-shelf parts.
The Integra upper comes complete with a VLTOR/BCM Gunfighter charging handle which is probably one of the best in today’s market. I don’t believe that it is marketed as such, but my Gunfighter CH that I use on my suppressed 5.56 AR’s seems to divert gas blowback away from the shooters face, an important part of shooting with a (standard) silencer mounted on an AR.
Looking through the M-LOK equipped Seekins rail, the short gas tube and unique gas block can be seen butted up against the rear end of the silencer tube. We will touch more on the gas block and barrel pinning in a little while. I was also happy to see the M-LOK system make an appearance on the Integra; initial mockups featured the now nearly defunct KeyMod attachments.
The G-Core is sleek and light – the approximately six-inch titanium monocore is precisely machined to fit flush inside the Integra’s tube. Sliding the core into and out of the tube for mounting is a piece of cake. Not being a machinist or engineer, the idea of manufacturing the core, tube and barrel to all work together for a precise and repeatable fit makes my brain hurt. However, the masters over at Gemtech obviously know what they are doing; the whole system comes together accurately every time.
The core’s threads are sharp and clean and the shoulder is flawlessly flat for a perfect mating surface onto the barrel’s shoulder.
Overall, after the initial inspection, the build quality of the Integra is exactly what you would expect to see from Gemtech – clean and precise.
Pure numbers don’t hold a lot of weight with my reviews, but they are an important starting point. Of course, everyone’s perceptions are different – what feels heavy to me might be light for you. The same goes for decibel metering; all things being equal, a suppressed gunshot might sound loud to me but respectably quiet to you.
However, quantifiable data is necessary to be able to give reportable information prospective buyers who can’t stand in the same forest or field and hear the shots or feel the blast themselves. So let’s knock this out.
- Caliber 5.56mm (.300BLK available).
- Sound Reduction:
- 131 dB (5.56mm)
- 128 dB (.300 Blackout with subsonic ammo)
- 5.56mm Barrel Length: 10.5″ (1:7 Twist)
- .300BLK Barrel Length: 11″ (1:8 Twist)
- Overall Integrated Length: 16.1″
- Weight: 5lbs
- Material Titanium tube, gas block and core
- Full Auto Rated
- Bolt carrier and charging handle included
- Seekins Handguard
Enough of the official data, what about the intangibles that can’t be quantified using weights and measures? Honestly, the Integra not only feels solid and well made, but it also is comparable to an unsuppressed short barreled upper in weight and a 16″ unsuppressed barreled upper in length. Which sounds obvious, until you remember that this is a compact package with no mounting systems and no need for an additional SBR tax stamp.
The titanium core adds very little weight to the end of the barrel, arguably the place where additional mass is least welcome. Also, the serialized silencer tube protrudes a little more than an inch from under the rail system.
Overall, Gemtech has done a great job in producing a well made upper/silencer combination that feels as natural as any other complete upper from a top tier manufacturer.
Let’s get the Integra out on the range.
Fielding the Gemtech Integra:
Being a complete upper receiver group, installing the Integra on your lower receiver is simple. Like with any standard AR15, with the bolt carrier group and charging handle installed and fully locked, retract the pins on your lower, line them up and press them home.
For my review I used a Noveske billet lower, a Geissele SD-E trigger and an H2 weight buffer. However, I did swap in an H-marked buffer for a 20 round function test to make sure the system worked with different recoil buffer weights. Without belaboring the simple test, both the H2 and H buffers functioned without issue. In fact, over the course of about three weeks and approximately 750 rounds, I did not experience a single malfunction.
But it wasn’t for lack of trying. If you are considering laying down nearly $2K on an integrally suppressed upper, you deserve to know the limits of the system. I decided from the beginning of the review that I was not going to baby the Integra – starting with ammunition selection. Over the course of my testing period, I used five ammunition types.
If you are a medium game rifle hunter, you are most likely familiar with Federal’s Fusion line of soft point .223 rounds. Currently at the top of the pile when it comes to terminal performance, the Fusion bullet is barrier blind and is in use by numerous law enforcement agencies across the U.S. as a standard duty round.
Once thought of as the pinnacle of tactical ammunition, Hornady’s 5.56mm Open Tip Match (OTM) TAP round is very accurate while still providing adequate expansion for defensive use.
Hornady’s steel-cased .223 TAP OTM round is ballistically similar to the 5.56mm pressure version, wrapped in a cheaper to manufacture package. These older rounds are bare steel and not lacquered like some steel-cased ammunition.
Not pictured are two types of full metal jacket (FMJ) rounds – a Federal .223 and unmarked Israeli surplus 5.56mm round.
No need to belabor the ammunition testing – the Integra ate everything up with easy with zero failure to function/failure to eject (FTF/FTE) malfunctions. Although I didn’t shoot for groups, I was able to achieve about 2-3 MOA level accuracy with the Fusion and two TAP arounds (the FMJ’s weren’t tested for precision or accuracy, just reliability and noise reduction). My quick and dirty MOA test is five rounds at 100 yards on a 4″ target with an estimated edge to edge measurement. I have no doubt that an experienced precision shooter could squeeze 1 MOA out of the Integra with a magnified optic.
With functioning, reliability and accuracy out of the way, we can finally start talking about suppression.
Luckily, this part is also fairly easy. The integra is very quiet for a 5.56mm round being suppressed out of a 10.5″ barrel. Is it the quietist I have ever heard? Hard to say. To date, the quietest 5.56 rifle I’ve had the pleasure of shooting was a MK12 with an Allen Engineering (AEM5) silencer. But of course, that rifle sports a ~17.5″ barrel, allowing for an additional seven inches of room for powder burn.
The majority of my testing took place in a wooded area with soft ground cover and temperatures in the the 50’s and 60’s. Although I must recommend hearing protection for any supersonic gunfire, I did remove my foam ear plugs for a few magazines to get an idea of raw suppression from the shooter’s perspective. Also, I could not discern a difference from any of the five types of ammunition I used during the review.
But yes, the Integra is very quiet for a suppressed 5.56mm rifle. Is it the quietest short-barreled AR15 ever made? I don’t know if I am qualified to make that conclusion. However, the blast and noise reduction is impressive enough to be able to acknowledge that ‘quietest ever’ is a real possibility.
There is a lot of technology going on behind the scenes on the Integra. From the G-Core, the pinned and welded gas block to the bore evacuator, the Gemtech has created a rifle platform centered on the user experience. What’s a ‘bore evacuator’? Standby.
The evacuator is a simple passive device. It consists of a ring of holes drilled into the barrel, surrounded by a cylindrical pressure reservoir. As the shell moves down the barrel during firing, it creates a high pressure in front of the projectile and the evacuator is filled with high pressure air, it reaches a point where the base of the shell passes the set of holes. The high-pressure is then released through these holes. As the shell continues down the barrel the pressure begins to drop, and then suddenly returns to near atmospheric pressure as the shell leaves the barrel. During this process the high-pressure air in the reservoir begins to blow back into the barrel towards the front of the gun tube. By aiming these holes forward, their exhaust causes the pressurized air to be blown forward and out of the barrel extracting fumes from the barrel.
Simply put, the evacuator relies on pressure changes within the barrel as the bullet passes down the bore to force gasses and particulate matter forward and out the muzzle rather than back into the action and towards the shooter.
The result is a pleasant shooting experience with very little “gas to the face” that is experienced with other silencers with excessive blowback. The result is a very clean action.
Of course, the G-Core gets hit with a lot of residue from all the gas being directed forward, which may explain why the Integra is built to be disassembled for cleaning by the end user. The majority of rifle silencers require little to no actual “cleaning” due to the inherent velocities and temperatures of the 5.56/.223 cartridge.
But I was very surprised at the lack of residue and debris after 750 rounds. The bolt carrier group and action looked like what I would expect an unsuppressed rifle to look like after the same firing schedule. I’d go far as to say that it was remarkably clean.
It’s also worth noting that part of the way through the review I decide to pull G-Core for a quick inspection. I was concerned that the heat an debris would foul the monocore and tube enough to prevent a carefree maintenance extraction.
However, the core came out easily with the same tools and force needed when the Integra was brand new. Nice work, Gemtech.
The one real downside I found with the Integra was heat management. After two rapid fire 30 round magazines, the handguard was too hot to hold, forcing me to switch to a magwell support hand position.
However, this fact really shouldn’t surprise veteran silencer shooters – we all know that rifle cans get really hot, really fast. Luckily I was able to start a review of a vertical foregrip during my time with the Integra, solving the heat issue. Since I don’t normally use a VFG, I also considered using my Cole-Tac suppressor cover as a heat shield for a more natural grip.
I have no problem saying the Integra is an advanced system. But I go back and forth in my thinking that it should be reserved for silencer veterans versus beginners. On one hand, the 16.1″ upper will always be a 16.1″ upper – there’s no silencer to remove to make a compact unsuppressed rifle.
On the other hand, the Integra is plug-and-play, with little more to do than have a quality AR lower ready for shooting. There’s no need for buffer weight testing or adjustable gas blocks to adjust cycle rates for reliability. Gemtech has done all of that work for you up front. Plus, no SBR NFA tax.
So, even as I write this review, I still haven’t made up my mind on the ideal consumer for the Integra. Which means it is going to come down to your specific use case. Hunting? Defense? Range/Tactical? Yep, there’s room for everyone with the Integra.
If I was in the market for a 5.56 AR suppressor, I would absolutely consider the Gemtech Integra. It’s very quiet, runs clean and is engineered to just plain work. In addition, Gemtech is known for solid customer service should the need arise. And don’t forget, no Form 1 NFA application and no extra $200 tax for an SBR.
If you are a 300BLK junkie (I am not, yet) the Integra comes chambered in that caliber as well, giving you the option of subsonic ammunition. No doubt some of my Silencer Shop Authority brethren are testing that version as we speak.
If I was allowed to play engineer fantasy camp in the Gemtech test kitchen, I’d like to see if we could get the Integra even quieter. My first thought would be to extend the barrel out to 12.5″, giving time for a more complete powder burn before entering the silencer itself. With this, I might try extending the silencer tube out to 18″ to keep the internal volume on par with its current design. Besides the additional 2″ length being barely noticeable to most shooters, the added velocity over a 10.5″ setup will help with better terminal ballistics. And the the whole package should be even quieter than it is now. But until Gemtech decides to call me up to the majors, I’ll stick with my keyboard and my ideas.
And now to break down 3,000 words into bullet points.
- Handguard heat management under moderate to heavy firing schedules
- Price – yes, it’s on the expensive side, but you get a lot for your money
- Very Quiet
- Very Clean
- Plug and play design that just plain works
- Extreme fun levels
Thanks for reading. See you for the next Silencer Shop Authority review here at Modern Rifleman
The GEMTECH INTEGRA upper series is the most advanced Integrally Suppressed Upper Receiver available. We have teamed up with NEMO Arms to create the smallest and easiest to maintain package the world has ever seen. The INTEGRA utilizes GEMTECH’s proven G-CORE Technology that is removable, cleanable, and replaceable while still bringing the best sound reduction of any similar sized package. The GEMTECH/NEMO Arms patented gas block eliminates blowback, making this upper receiver more comfortable to shoot.
5.56 OR 300BLK