Good morning everyone and welcome back to another quiet edition of TFB’s Silencer Saturday brought to you by Yankee Hill Machine, manufacturers of the Resonator and Resonator K line of 7.62mm suppressors. Last week we ventured off into DIY land with a primer tutorial on how to build your own Form 1 suppressor (hint: start with an approved ATF Form 1). As soon as my government permission slip comes back stamped, we’ll get to work. This week we look at the professionally manufactured Rex Silentium MG7 K 5.56mm rifle silencer. How quiet was the MG7 K? Lean in and I’ll tell you.
SILENCER SATURDAY #122: Quiet 5.56 With The Rex Silentium MG7 K
We’ve talked about barrel length as it relates to suppression, well, at-length over the years. Achieving a full (or as much as possible) powder burn inside the barrel helps to tame those expanding gases at the muzzle. A longer barrel can also reduce the blow-back of gas and debris back down the barrel and out the action near the shooters face. And a longer barrel physically pushes the muzzle farther away from the shooter’s ear.
Since supersonic .223/5.56mm will never be “quiet” like our subsonic gun and ammo pairings and since I don’t have a decibel meter for testing, I wanted take advantage of every sound hack available to compare suppression to my ears. For a non-scientific comparison, I used my 2” OD Form 1 suppressor that is the second quietest 5.56mm silencer I own (the first being the Allen Engineering AEM5).
Previous Rex Silentium TFB Coverage:
- SILENCER SATURDAY #118: Suppressing Rimfire With The Rex Silentium SEG
- SILENCER SATURDAY #115: Catch The Subsonic Virus – Rex Silentium MG10
- New Pew Pew: Rex Silentium COV 22 – Covert 22LR Mini Suppressor
- Rex Silentium Gen2 Suppressors (Honoris, Viribus and Fidelis)
- Tubeless & Fully Welded
- Industry Standard 1.375-24 Main Thread Mount
- 100% 17-4PH Stainless Steel Hardened to 45-47Rc at 190,000psi Tensile
- 5.6″ Overall length
- 1.70″ Diameter
- Unique RAW Flat Bronze Heat Treated Finish
- Full Auto Rated
- No Barrel Length Restrictions
- Easy to Recore
- Lifetime, No BS Warranty
- $499 (sale price)
223 Remington (5.56 NATO)
- 10.5″ Barrel: 136.35 dB
- 24″ Barrel: 133.52 dB
Standing on the shoulders of the GEN3 Honoris Rifle Suppressor, the MG7 pushes the suppression-centric design further. Now in a tubeless embodiment, we have leveraged the years of development and testing to craft a tough, light and above all, quiet suppressor.
The MG7 was designed for more discreet and tactical use. It is a compact, light and stout package for maximum suppression of subsonic rifle, pistol and small case supersonic rifle cartridges. Though, if you wish, you can put it on anything of magnum stature, just don’t expect the sound reduction like its big brother, the MG10 Ultra Rifle Suppressor. Ready for extreme full auto, the MG7 is not just a tactical rifle suppressor, it is quite happy on your hunting rifle too. The light weight and easy maneuverability make it great in the field.
Backed by our lifetime, no bullshit warranty we designed the MG7 to be easily recored should you ever have any problems. The serial number and engraving is at the very back of the suppressor body. This is the safest place in the event of a baffle strike. If you ever damage to the suppressor we can recore it fast and return it to factory new condition in a matter of days.
Precision CNC machined from 100% 17-4PH stainless steel, fully welded then hardened to the max. The final result is a suppressor with a hardness of 45-47Rc and tensile strength of 190,000psi. Go ahead… mag dump, bump fire or swing your selector to full auto. This suppressor is ready to last a lifetime or two or three!
In addition to the design of the suppressor itself, we also made our assembly systems easily adaptable to custom orders. If you need a special bore size for your host firearm or even a special length, we can build it for you. Our manufacturing cells are flexible enough to accommodate one-off custom assemblies. We can even customize your serial number.
The MG7 and all of our rifle suppressors are compatible with industry standard quick disconnect (QD) mounts. The main thread on the back of the suppressor is 1.375-24. There are many options for QD mounts on the market.
Testing The Rex Silentium MG7 K
For today’s testing I used the included 1/2×28 direct thread adapter. One of the great aspects of the MG7is that it uses the defacto industry standard of 1-3/8”x24. This means if you like the cherry bomb, the KEYMO or any of the other manufacturer’s mount options with the same specs, you are in luck. Swap at will.
- Lower Receiver: Noveske
- Upper Receiver: VLTOR
- H2 buffer weight
- Trigger: Geissele SD-E Super Dynamic – Enhanced Flat Blade
- Barrel: 17.5” MicroMOA 5.56 barrel with three-position MicroMOA gas block
- Optic: Maven 5-30×54 RS.4 (on loan & unreleased – review underway)
- Optic Mount: Spuhr 34mm Cantilever (on loan – review underway)
- Tripod: Really Right Stuff TFCT-24L SOAR with ANVIL ball head (purchased – review underway)
A quick note about the RRS tripod: I’ve used my $50 tripod rest for about 8 years. While it served its purpose, now knowing how solid a real tripod can be, I should have made the jump years ago. No more balancing acts or wobbles – the RRS SOAR line feels like a life changer already.
At just over 12 ounces, the Rex Silentium MG7 isn’t the lightest 5.56mm suppressor on the market, but it’s no slouch either. I didn’t notice it much on the end of the long barrel.
The exit bore of the MG7 seems tight compared to other 5.56mm suppressors (the Delta P Brevis having the closest bore tolerance in my lineup). The smaller the bore, the better suppression, but also the more potential for gas and debris blowback into the action or at the shooter’s face. I’ll get a proper measurement prior to sending it back home to Montana.
I used all three gas settings on the MicroMOA gas block: normal, suppressed, and adverse and did not have any issues with cycling with at of them with the MG7 mounted.
As for suppression levels, I was impressed. While the MG7 did not rise up and unseat the AEM5 king, it did produce a nice quiet report. Yes, a non-scientific test that results in a ‘quiet report’ designation is not exactly useful. However, I’ve shot a lot of suppressed 18” 5.56mm ARs and this setup ranks close to the top. I still can’t recommend ditching the hearing protection on any supersonic round, but the MG7 does have a pleasant, hushed tone. I’d classify it to close to a suppressed .22LR pistol using supersonic ammunition.
Overall, I think there is very good value in the Rex Silentium silencers: they are well made, quiet when paired with the right host and they feature a near-universal mounting system thread pitch.
Thanks for reading everyone. Stay safe and healthy and we’ll see you here next week for another edition of TFB’s Silencer Saturday.
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