Good afternoon everyone and welcome back to TFB’s Silencer Saturday brought to you by Yankee Hill Machine, manufacturers of the YHM R9 suppressor. I would like to thank Austin for last week’s awesome review of the B&T RBS suppressor, enduring heavy duty beltfed punishment, while I was away on business. In the interim, a factory fresh SIG SLX 5.56 QD rifle suppressor arrived for review. How does it differ from the SIG SLH models that we have reviewed in the past and should you invest in one for your AR-15 or SIG MCX? Let’s take a look.
The new SIG suppressors are made by additive manufacturing (3D printing) and come in two designs: SLH and SLX. What is the major difference between the SIG SLH and SIG SLX Suppressors?
- SIG SLX Suppressors: Supersonic performance focus, low toxicity, flash reduction.
- SIG SLH Suppressors: Subsonic performance focus, low toxicity, superior noise reduction.
For a supersonic only round like 5.56, the gas multi-flow design of the SLX models will help with cycling, rates of fire, and reduced gas blowback. Let’s face it, a 5.56 AR-15 will never be hearing safe – so focusing on gas flow and reduced blowback is a smart choice.
Each of the two models have sub-classifications that indicate caliber, mounting systems, and the type of metal used (inconel steel alloy or titanium alloy). All of them are available in black and some are available in FDE.
SIG SAUER @ TFB:
- SILENCER SATURDAY #215: SIG Sauer SLH300TI & SLH762 Suppressors
- SILENCER SATURDAY #213: Blizzard! SIG Sauer SLH Suppressor Preview
- TFB Review: Switchblade AR Pistol from SIG SAUER
- The Switchblade: SIG SAUER Announces New M400 Series AR Pistol
- 0:00 Intro
- 0:43 Sig Moving to 3D Printed Suppressors Only
- 2:05 MOD-X Modular Pistol Silencer
- 2:36 Shooting the MOD-X
- 7:43 SLH and SLX Rifle Suppressors
- 8:24 Shooting the SLH with Super- vs. Subsonics
- 10:15 The Taper Mount and Clutch Lock Systems
- 12:40 Full Auto Shooting the MCX/SLH Combo
- 12:50 SLH/SLX Toxic Gas and Flash Reduction
- 14:37 Shooting the SLX in Full Auto
- 14:54 Titanium vs. Inconel Steel
- 15:25 Short Burst from the LMG68 and SLX Can
- 15:36 SLH vs. SLX – Which One to Get?
- 17:17 Shooting SLX with the MCX Spear
- 17:27 Pricing and Availability
- 18:08 Full Auto Shooting the MCX/SLX Combo
- 18:20 Durability
- 18:58 Conclusion
SILENCER SATURDAY #220: The SIG SLX 5.56 QD Rifle Suppressor
At the risk of being labeled an absolute SIG shill, my favorite semiautomatic platform is the MCX. Besides being a perfect suppressor host with an adjustable gas system, the SIG MCX makes for a compact PDW that is accurate and dependable. Unfortunately I don’t have a 5.56 MCX or upper to test the SLX556-QD. However SIG was nice enough to lend me an M400 Switchblade pistol to pair with their new silencer.
The SIG Switchblade is not an AR-15 I would have pulled off the rack and bought on my own, but it is pretty impressive. Light, compact, affordable, ambidextrous controls all go towards making this a handy farm/ranch gun. It’s no MCX, but it definitely punches above its weight. As evidence, I’ll be buying this one for myself.
- MSRP: $1399
- BUY NOW: GUNS.COM
- OWNERS MANUAL: https://www.sigsauer.com/media/sigsauer/resources/M400.pdf
- SKU: PM400-SDI-11B
- CALIBER: 5.56 NATO
- BARREL LENGTH: 11.5 in [292 mm]
- MAGS INCLUDED: (1) 30rd Polymer Mag
- MAG TYPE: AR-15
- ACTION TYPE: Semi-Auto
- STOCK TYPE: Magpul BSL Brace
- BARREL MATERIAL: Stainless Steel
- TRIGGER TYPE: 2 Stage Matchlite Duo
- TWIST RATE: 1:7
- FOREND TYPE: Alloy
- GRIP TYPE: Polymer
- RECEIVER FINISH: Cerakote Elite
- OVERALL LENGTH: 30 in [795 mm]
- OVERALL WIDTH: 2.5 in [63.5 mm]
- HEIGHT: 7.5 in (191 mm)
- ACCESSORY RAIL: M-LOK
- OPERATING SYSTEM: Direct Impingement
The SLX series of rifle suppressors feature the new Clutch-LOK QD mounting system which is easy to use, repeatable, and extremely durable. The internal multi-flow path within the SLX suppressors allows gasses to exhaust at a faster rate than traditional baffle-style suppressors. This results in 70-80% less toxic fumes flowing back through the ejection port into the shooter’s face. The SLX series is a performance-based suppressor designed for use with supersonic ammunition and ideal for users focused on flash reduction and lower toxic fumes. The new low-tox SLX suppressors deliver a superior shooting experience, unlike any other suppressor.
The internal multi-flow path of the SLX with low resistance exhausts gases at a faster rate than traditional baffles. SLX features 70-80% less PPM than traditional baffle suppressors.
The SLH and SLX suppressors all come with the new Clutch-LOK QD mounting system and muzzle brake mount. The brake portion of the mount is timed independently of the muzzle device that is secured to the to the barrel threads and taper surfaces. I wasn’t a fan of this device in the last review, but now that I have mounted them all a few different times, it’s growing on me. For simplicity, I still prefer a flash hider on most semiautomatic short barreled firearms.
- Manufacturer’s Page: https://www.sigsauer.com/slx-suppressor.html
- In stock @ Silencer Shop
- MSRP: $1480
- Model: SLX556-QD
- Caliber: 5.56 NATO
- Materials: Inconel
- Diameter: 1.67 in (42 mm)
- Length: 7.4 in (188 mm)
- Weight: 19.4 oz (550 g)
- Mounting system: Clutch-Lok QD
Additive manufacturing allows for a few advantages over traditional metalworking. Internal geometries can be much more complex and efficient, increased strength (no welds to fail), and potential weight savings are all at the top of the list. One of the areas that does not impress me about the SIG SLX 5.56 QD is its weight. At nearly 20 ounces it is in the ‘nearly heavy’ category of AR-15 suppressors. On a short barrel like the M400 Switchblade, it’s not an issue, but stretch it out on a 16” barrel and you are going to feel it.
My next concern with the SIG SLX is its price. An MSRP of $1500 is in the upper range for AR-15 suppressors and may keep many of you on the sidelines. Additive manufacturing is expensive and there is no way around that for the time being. To be successful, printed suppressors need to offer additional benefits to attract buyers. The multi-flow geometry is one of the huge benefits of this advanced manufacturing process.
I experienced none of the usual gas blowback, gas to the face, or toxic gases that come with a lot of top shelf direct impingement AR-15 suppressor setups. This rifle cycles smoothly and reliably. As we know, semiautomatic 5.56 will never be considered quiet by any metric, but the SIG SLX does perform beautifully, suppressing the M400 Switchblade to bearable levels. Don’t forget your hearing protection.
Price and weight. This are my two potential detractors for the SLX556 QD. Outside of those two categories, this is well made and “quiet” 5.56 suppressor. The multi-flow design does its job very well, keeping back pressure and gas blowback to the lowest levels possible. SIG has done a fantastic job with their new suppressor lineup, now we just need to finish the review of all three cans with some full auto testing. Yes, I’ll get video.
Be safe, have fun, and we’ll see you back next weekend for another Silencer Saturday.