5.56mm / 6mm Arc suppressor
Liberty Precision Machine · 5.56mm / 6mm Arc
$869
MSRP
Specs on the box
Mounting
Build & use
Sound
116.9
LIAeq100ms (dB)
Muzzle · 14.5" AR-15 · 5.56 Lake City M193
Backpressure
−4.0
Change in cycle time (ms)
Primer strike → bolt closed, vs bare host
Flash
Not yet tested
Metric TBD
Stand-in — not yet defined
Add to Gauge
SCOUT REPORT
Built before 3D printing changed the industry, this suppressor uses a traditional welded baffle stack, and it was ahead of its time. It showed just how much a welded design could do to reduce backpressure if some skill and creativity be applied. Newer options have since arrived, but this stainless steel can still holds its own against modern suppressors. Its interchangeable vented and sealed end caps add versatility. Run the vented cap on a semi-auto host to take advantage of the lower backpressure, then swap to the sealed cap on a manually cycled firearm for better sound performance. While I have newer can's in my safe, this one still finds it's way onto my range guns as a pleasant low backpressure work horse. **Disclaimer** This test diverge from the standard test configuration with the use of a DA Xeno OmniBrake and Xeno Mount
Scout Report
Metered August 20, 2026
Our take
This suppressor holds it own with a high degree of adaptability. The vented shows itself to handle the high pressures of the 10.5" really well and holds flat at the 14.5" mid gas indicating this suppressor was made with higher pressure in mind. It still holds up well on the 18" barrel and has the added perk of a solid end cap that pairs will with this longer barrel length. See the Solid end cap configuration for details.
Sound sweep
| Metric | 10.5" AR-155.56 Lake City M193 | 14.5" AR-155.56 Lake City M193 | 18" AR-155.56 Lake City M193 | |||
|---|---|---|---|---|---|---|
| SE | ML | SE | ML | SE | ML | |
| LIAeq100ms (dB) | 119.6 | 118.3 | 120.8 | 116.9 | 116.4 | 115.7 |
| Peak (dB) | 150.3 | 147.4 | 150.2 | 146.5 | 146.6 | 145.6 |
| Peak (dBA) | 147.7 | 142.8 | 141.1 | 140.7 | 138 | 138.9 |
| Impulse (Pa·ms) | 56.2 | 87.8 | 81.8 | 79.4 | 43.9 | 62.6 |
How to read this report
Our core performance metric is LIAeq100ms: the whole pressure curve, A-weighted to approximate the human ear, integrated over 100 ms. Peak and impulse are shown alongside for context. Every configuration is metered at SE (shooter's ear) and ML (muzzle, left side).
About the Test Platform
Suppressors are tested across a full range of barrel lengths and gas systems. See our article on the test platforms for full detail behind our test configurations.
The AR-15 hosts behind the 5.56 testsCold-can first shot
On the first shot, unburnt propellant mixes with the oxygen sitting inside the suppressor and burns a second time in the can. That secondary combustion often makes the round louder than the ones behind it. Once that oxygen is burnt off, follow-up shots settle into a quieter, steadier number. This is commonly called first round pop, or FRP. Because a hunter, marksman or defensive shooter may only ever fire one or two rounds, we isolate the first-round data rather than bury it in the average, and present it here. The magnitude of first round pop varies substantially across designs.
Shooter's ear · LIAeq100ms (dB)
| Host | First round | Subsequent | Pop |
|---|---|---|---|
| 10.5" AR-155.56 Lake City M193 | 119.8 | 119.6 | +0.2 |
| 14.5" AR-155.56 Lake City M193 | 120.7 | 120.8 | -0.1 |
| 18" AR-155.56 Lake City M193 | 116.7 | 116.4 | +0.3 |
Change in cycle time
Cycle time runs from primer strike to bolt closed. Backpressure drives the bolt home sooner, so a bigger drop versus the bare host indicates more backpressure and more wear.
Change in Cycle Time
−4.0 ms
Primer strike to bolt closed: 54.5 ms suppressed vs 58.5 ms bare host
Performance for its size
These metrics nest raw decibel performance in the important context of how well a suppressor performs for its size.
Quoted off 14.5" AR-15 · 5.56 Lake City M193. Each value is dB reduction ÷ the listed dimension, at shooter's ear (SE) and muzzle left (ML).
Per cubic inch (dB/in³)
| Suppressor | SE | ML |
|---|---|---|
| Torch HUB · thisestimated volume | 1.22 | 1.88 |
| Torch QDestimated volume | 1.22 | 1.88 |
Per ounce (dB/oz)
| Suppressor | SE | ML |
|---|---|---|
| Torch HUB · this | 1.1 | 1.69 |
| Torch QD | 1.1 | 1.69 |
Per inch (dB/in)
| Suppressor | SE | ML |
|---|---|---|
| Torch HUB · this | 2.49 | 3.82 |
| Torch QD | 2.49 | 3.82 |
Tuned vs untuned
This metric captures the tuning overhead of the suppressor when paired with sound-mitigating part choices. A valuable metric for understanding what overhead you, the end user, have to push the performance envelope. Both rows are the same barrel and the same load. Only the parts used change.
How we tuned
Riflespeed Gas Block plunger #917. Buffer configured with H2 and sprinco white spring.
| Metric | 14.5" AR-155.56 Lake City M193 | 14.5" AR-15 Tuned5.56 Lake City M193 | DifferenceTuned − untuned | |||
|---|---|---|---|---|---|---|
| SE | ML | SE | ML | SE | ML | |
| LIAeq100ms (dB) | 120.8 | 116.9 | 116.3 | 116.3 | -4.5 | -0.6 |
| Peak (dB) | 150.2 | 146.5 | 149.7 | 144.7 | -0.5 | -1.8 |
| Peak (dBA) | 141.1 | 140.7 | 144.5 | 137.8 | +3.4 | -2.9 |
| Impulse (Pa·ms) | 81.8 | 79.4 | 41.2 | 81 | -40.6 | +1.6 |
Same host, different loads
| Metric | 14.5" AR-155.56 Lake City M193 | 14.5" AR-155.56 Lake City M855 | 14.5" AR-155.56 Black Hills OTM 77gr | |||
|---|---|---|---|---|---|---|
| SE | ML | SE | ML | SE | ML | |
| LIAeq100ms (dB) | 120.8 | 116.9 | Not yet tested | Not yet tested | 118.9 | 114.3 |
| Peak (dB) | 150.2 | 146.5 | Not yet tested | Not yet tested | 148.4 | 144.1 |
| Peak (dBA) | 141.1 | 140.7 | Not yet tested | Not yet tested | 139.1 | 135.8 |
| Impulse (Pa·ms) | 81.8 | 79.4 | Not yet tested | Not yet tested | 63.7 | 60 |
No image available  | No image available  | No image available  | ||||
Check Price
Links above point to third-party sites. SilencerScout does not control their content and earns no affiliate commission from these review links.
SilencerScout