SSS.6.100 - Dead Air Nomad-30 (1st Gen) and the MK18 5.56x45mm Short Barrel Automatic AR15 Rifle (Free Version)

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Dead Air Nomad-30 (1st Gen) on the MK18 5.56x45mm AR15 with 10.3-in Barrel

The Nomad-30 is designed by Dead Air. It is a 30 caliber centerfire rifle silencer, intended to suppress most cartridges with projectiles appropriately sized to travel through the bore, including 300 Norma Magnum. It has a 1.74-inch diameter and is 6.5 inches in length when using the direct-thread adapter. The user may choose to use other Dead Air or third-party adapters compatible with the 1.375”-24tpi system. The silencer is tubeless; the baffles are constructed of 17-4 stainless steel, with the endcap constructed of Grade 5 titanium. The silencer weighs 14.4 ounces with the direct thread mount, as tested. The Nomad-30 can be obtained from Silencer Shop.

This Sound Signature Review contains single-test results using the Dead Air Nomad-30 (1st Gen) with the direct thread mount on the MK18 Automatic AR15 rifle, chambered in 5.56x45mm NATO with a 10.3-inch barrel. Federal XM193 55gr ammunition was used in the test. The standard PEW Science MK18 test host weapon system is described in Public Research Supplement 6.51.

Nomad Version Notes: The Nomad-30 was originally released in 2018. During its product life, Dead Air has implemented successive manufacturing and performance improvements to the silencer’s design. The data in this review can be considered by the reader to be a lower bound representation of Nomad-30 performance on the tested weapon system, with regard to sound suppression metrics. The Nomad-Ti is also available from Dead Air, which is constructed from Grade 5 titanium and lowers the system weight by over 4 ounces. Current Nomad-30 and Nomad-Ti units incorporate the latest internal design improvements. Publication of Nomad-Ti 5.56x45mm test data by PEW Science is forthcoming.

  • Section 6.100.1 contains the Nomad-30 test results and analysis.

  • Section 6.100.2 contains Suppression Rating comparisons of the Nomad-30 with dedicated 223 and 30 caliber silencers on the current market, including the YHM Turbo T2, Dead Air Sandman-S, HUXWRX FLOW 556k, Energetic Armament ARX, KAC QDSS-NT4, Rugged Razor556, Otter Creek Labs Polonium and Polonium-K, Surefire SOCOM556-RC2, HUXWRX HX-QD 556 and HX-QD 556k, Q Trash Panda, CGS Helios QD, SilencerCo Saker 556, Rugged Razor762, and others.

  • Section 6.100.3 contains the review summary and PEW Science subjective opinions.

Summary: When paired with the 10.3-in barrel MK18 and fired with Federal XM193, the Dead Air Nomad-30 (1st Gen) mounted with the direct thread mount achieved a composite Suppression Rating™ of 27.9 in PEW Science testing. As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.

The supersonic .308 performance of the Dead Air Nomad-30 (1st Gen) is detailed in previous Sound Signature Review 6.43, in which it achieved a Suppression Rating of 37.6.

Relative Suppression Rating Performance is Summarized in SSS.7 - PEW Science Rankings

6.100.1 Dead Air Nomad-30 (1st Gen) Sound Signature Test Results

A summary of the principal Silencer Sound Standard performance metrics of the Dead Air Nomad-30 tested with the direct thread mount is shown in Table 1. The data acquired 1.0 m (39.4 in) left of the muzzle is available for viewing to all. The data acquired 0.15 m (6 in) right of the shooter’s ear is only available to membership supporters of PEW Science and the Silencer Sound Standard. You can support PEW Science testing, research, and development with a membership, here. State-of-the-art firearm sound signature testing and research conducted by PEW Science is supported by readers like you.

 

Table 1. Dead Air Nomad-30 (1st Gen) Sound Metric Summary

 

6.100.1.1 SOUND SIGNATURES AT THE MUZZLE

Real sound pressure histories from a 6-shot test acquired with PEW-SOFT™ are shown below. Six cartridges were loaded into the magazine, the fire control group positioned to single-shot, and the weapon was fired until the magazine was empty and the bolt locked back on the follower of the empty magazine. Only five shots are considered in the analysis. The signatures of Shot 6 are displayed in the data presentation but are not included in the analysis to maintain consistency with the overall PEW Science dataset and bolt-closing signatures. The waveforms are not averaged, decimated, or filtered. The data acquisition rate used in all PEW Science testing is 1.0 MS/s (1 MHz). The peaks, shape, and time phasing (when the peaks occur in relation to absolute time and to each other) of these raw waveforms are the most accurate of any firearm silencer testing publicly available. PEW-SOFT data is acquired by PEW Science independent testing; the industry leader in silencer sound research. For more information, please consult the Silencer Sound Standard.

The primary sound signature pressure histories for all 6 shots with the Nomad-30 are shown in Figure 1a. The sound signatures of Shot 1 and Shot 2 are shown in Figure 1b, in early time. The real sound impulse (momentum transfer potential) histories from the same 6-shot test are shown in Figure 2a. In Figure 2b, a shorter timescale is shown comparing the impulse of Shots 1 through 5.

Fig 1a. Dead Air Nomad-30 (1st Gen) 5.56x45mm NATO MK18 Automatic Rifle Muzzle Sound Pressure Signature

Fig 1b. Dead Air Nomad-30 (1st Gen) 5.56x45mm NATO MK18 Automatic Rifle Sound Pressure Signature

Figure 2a. Dead Air Nomad-30 (1st Gen) 5.56x45mm NATO MK18 Automatic Rifle Muzzle Sound Impulse Signature

Figure 2b. Dead Air Nomad-30 (1st Gen) 5.56x45mm NATO MK18 Automatic Rifle Muzzle Sound Impulse Signature

The Dead Air Nomad-30 exhibits measurable first round pop (FRP) on this platform, as shown in the ancillary pressure jetting (Figure 1b) and faster rise to a greater positive phase impulse (Figure 2). However, the FRP signature is not postulated to result in a significantly increased inner ear damage risk to bystanders when compared to the signature of subsequent shots. It is interesting to note that on this 5.56x45mm weapon system, the Nomad-30 exhibits a similar shaped impulse history at the muzzle to that generated by the same silencer on a 7.62x51mm weapon system with twice the barrel length. Reference Figure 4 of the 7.62x51mm Dead Air Nomad-30 Test Report (Review 6.43). The FRP differential in the two combustion regimes is similar. Rarefaction results in a steeper decay in this MK18 test (31.2 ms, Figure 2b), which shortens the effective FRP impulse positive phase duration differential. This relatively expedient impulse decay is one of the reasons the severity of the Nomad’s FRP signature is postulated to be reduced, for its gross amplitude.

PEW Science Research Note 1: Another similarity between the measured test data with this silencer on the 5.56x45mm platform and the previous 7.62x51mm platform is the early time pressure signature, prior to combustion gasses exiting the silencer. This internal combustion signature is shown in Figure 1b beginning at a time of approximately 29.9 ms. The Nomad-30, as well as the Dead Air Nomad-Ti, exhibit this signature fingerprint in multiple combustion regimes. Note the similarity of these fingerprints of the Nomad-30 and Nomad-Ti in Figure 8a of the 7.62x51 Dead Air Nomad-Ti Test Report (Review 6.44), in which the signatures of the two silencers are overlaid. The presence and consistency of these signature characteristics, across silencer models and combustion regimes, demonstrates the consistency of PEW Science testing and analysis in accordance with the Silencer Sound Standard. It also demonstrates how consistently sound transmission occurs through the blast chamber geometry of the Dead Air Nomad design, regardless of material.

PEW Science Research Note 2: Unlike in the test of the Dead Air Sandman-S on the MK18 (Review 6.92), the Dead Air Nomad-30 is able to control secondary combustion propagation from the 10.3-in 5.56x45mm barrel, as observed in the impulse decay histories shown in Figure 2. Recall that in Figure 2 of the Sandman-S test report, the signature of Shot 4 and later shots became highly erratic. The Nomad-30 does exhibit erratic behavior beginning in Shot 4, above, but not nearly to the degree of the Sandman-S. PEW Science postulates this is a consequence of the more advanced design features of the Nomad series of silencers, when compared to that of the Sandman series; the Nomad baffles possess coaxial elements allowing for further high pressure gas routing later in the shot string, whereas the Sandman baffles are more primitive, usually producing significant pressure stagnation zones in these combustion regimes. A parallel can be drawn between the technical performance differential of the Sandman-S and Nomad-30, by using the Q Trash Panda MK18 data (Review 6.61) and CGS Helios QD MK18 data (Review 6.66). All four of these silencers are over-bored for the cartridge. Only the silencers with highly advanced coaxial baffle elements (the Nomad-30 and Helios QD) are able to control secondary combustion on the short barrel MK18. The Sandman-S and Trash Panda are unable to suppress secondary combustion, as effectively, in this combustion regime. As demonstrated throughout the Silencer Sound Standard, design elements of supersonic rifle silencers can have significant performance consequences. It is important to note that despite the erratic signatures that result from the Q Trash Panda on this platform, its suppression performance, overall, eclipses that of the Nomad-30. MK18 suppression performance comparisons are provided in Section 6.100.2, below.

The flow rate of the Dead Air Nomad-30, like most over-bored silencers, is higher than that of dedicated silencers for the cartridge. For example, the YHM Turbo T2 (Review 6.98), Otter Creek Labs Polonium (Review 6.75), Polonium-K (Review 6.95), Surefire SOCOM556-RC2 (Review 6.52), SilencerCo Saker 556 (Review 6.53), and KAC QDSS-NT4 (Review 6.78) all possess lower flow rate (higher back pressure) than the Dead Air Nomad-30 on the MK18 weapon system.

PEW Science Research Note 3: It should be noted that although the Dead Air Nomad-30 is a 30 caliber rifle silencer, it produces significantly higher back pressure on the MK18 than silencers exhibiting very high flow rates, such as the OSS HX-QD 556 (Review 6.54), OSS HX-QD 556k (Review 6.64), and the HUXWRX FLOW 556K (Review 6.83).

PEW Science Research Note 4: As in all semiautomatic AR15 weapon testing, a second pressure pulse originates from the ejection-port signature of the weapon and it occurs early enough in time such that its waves coalesce with that of the muzzle signature. However, in late time (at approximately 85 ms in Figure 1a) the mechanical noise of the bolt closing is observed. The pressure signature of Shot 6 does not display this event due to the bolt remaining open after the sixth and final round is fired from the magazine.

PEW Science Research Note 5: The closing time of the MK18 bolt is directly related to the flow restriction of a silencer for a given weapon system. PEW Science has determined bolt closing time variation from the unsuppressed state to be a reliable indicator of silencer back pressure, with strong correlation with the PEW Science Back Pressure Metric, Omega. However, PEW Science has also determined that the indicator is unreliable upon upper receiver fouling. Sound signatures are not influenced by this fouling, as these kinematics occur in late time, after gas venting to atmosphere. Momentum transfer, weapon condition (upper receiver fouling), and other factors, can significantly influence bolt closing time. PEW Science urges the reader to exercise extreme caution if using the published bolt closing time to make determinations regarding silencer flow restriction (back pressure) or weapon system kinematics. This type of calculation may provide erroneous results, as the weapon condition at the time of each test is not published data. The time-scale duration showing bolt closing time is only published by PEW Science such that the signature data pedigree may be verified.

The shape, timing, and magnitudes of the early-time pressure pulses and overall shape of the impulse waveforms measured at the muzzle, from shot-to-shot, are relatively consistent, until the aforementioned late-time irregularities resulting from primary axial over-bore.

As typically indicated, first-round sound signatures always differ from subsequent shots, as the atmosphere within the silencer changes. The FRP phenomenon cannot always be shown by viewing only the peak sound pressure. This is one of the reasons why The Silencer Sound Standard requires examining multiple sound signature metrics. Ammunition consistency can play a role in the determination of FRP, however, the close examination of measured pressure and impulse waveforms typically excludes ammunition from the possible factors influencing true FRP, due to the relative consistency of most high quality factory ammunition.

PEW Science Research Note 6: Note that the muzzle Suppression Rating of the Dead Air Nomad-30 with the direct thread mount is 26.3 and the shooter’s-ear Suppression Rating is 21.4; the same zone on the Suppression Rating Dose Chart. The higher flow rate of the 30 caliber Dead Air Nomad-30 assists with reducing ejection port signature, but it is not high enough to significantly decrease the overall severity of the signature to the shooter on the standard MK18 weapon system. Holistic suppression performance comparisons on the MK18 weapon system are examined in the section below.

6.100.2 Suppression Rating Comparison (5.56x45mm from the MK18)

Figure 5 presents a comparison of the PEW Science Suppression Rating of the Dead Air Nomad-30 (1st Gen) with the direct thread mount to that of other rifle silences on the MK18 automatic AR15 rifle. The standard PEW Science MK18 test host weapon system is described in Public Research Supplement 6.51.

Figure 5. Suppression Rating Comparisons of the Dead Air Nomad-30 (1st Gen) and other silencers, Using PEW-SOFT 5.56x45mm Supersonic Test Data and PEW Science Analysis

From the above data, it can be concluded that the Dead Air Nomad-30 possesses MK18 sound signature suppression performance to bystanders that is on par with that of the KGM R556 (Review 6.60), Q Trash Panda (Review 6.61), KAC QDSS-NT4 (Review 6.78), and HUXWRX (OSS) HX-QD 556 (Review 6.54). The hearing damage risk, to bystanders, is similar when using these four silencers on the 10.3-inch barrel MK18 AR15 short barrel rifle.

The Dead Air Nomad-30 significantly outperforms the Dead Air Sandman-S (Review 6.92) in MK18 suppression performance to bystanders. It does this both in pure suppression performance and suppression performance consistency. As previously stated in Section 6.100.1.1, a parallel can be drawn between the technical performance differential of the Sandman-S and Nomad-30, by using the Q Trash Panda MK18 data and CGS Helios QD MK18 data (Review 6.66). All four of these silencers are over-bored for the cartridge. Only the silencers with highly advanced coaxial baffle elements (the Nomad-30 and Helios QD) are able to control secondary combustion on the short barrel MK18 through the shot string. The Sandman-S and Trash Panda are unable to suppress secondary combustion, as effectively, in this combustion regime. Again, nonetheless, despite the erratic signatures from the Q Trash Panda on the MK18, its overall sound signature suppression performance eclipses that of the Nomad-30 on the MK18.

At the shooter’s ear, the Dead Air Nomad-30 produces a hearing damage risk on par with many other silencers on the MK18. PEW Science testing, analysis, and research indicates that without significant flow rate increases on the MK18 host weapon, coupled with favorable muzzle signature suppression characteristics, suppression performance at the shooter’s ear will not approach higher levels. The short barrel MK18 weapon system, when suppressed, still presents significant hazard to the weapon operator.

PEW Science Research Note 8: It is worth noting that the relative performance of rifle silencers can significantly change across combustion regimes, even when the projectile velocity is supersonic. It is again useful to compare the suppression performance of the Q Trash Panda, CGS Helios QD, and Dead Air Nomad-30. On a standard hunting rifle (20-in barrel 7.62x51mm), the performance of both the Helios QD and Nomad-30 eclipses that of the Trash Panda. The combustion regime, being of both high pressure and duration, is more efficiently suppressed with the coaxial design elements in the CGS and Dead Air silencers. On a short-barrel carbine (10.3-in barrel 5.56x45mm), the combustion characteristics are significantly different, and so are the performance differentials between the silencers. Small arm weapon system suppression performance is holistic and varies with cartridge, barrel length, and silencer design.

PEW Science Research Note 9: Another notable performance comparison shown in Figure 5 is that of the YHM Turbo T2 (Review 6.98) and the Dead Air Nomad-30. The YHM Turbo T2 does have higher flow restriction (more back pressure) than the Dead Air Nomad-30. However, despite that behavior, the two silencers produce extremely similar hearing damage risk potential to the MK18 weapon operator. The similar performance at the shooter’s ear with these two silencers on the MK18 is a function of muzzle signature differential and wave coalescence. An operator may experience more “blowback” on the MK18 with the YHM Turbo T2 than with the Dead Air Nomad-30, which is one symptom of higher backpressure. Nonetheless, a significant proportion of the blowback phenomenon occurs in late time; the hearing damage risk potential primarily being an earlier time phenomenon. It is for this reason that users should be cautious in their expectations of reduced back pressure improving signature at the shooter’s ear. It is not until silencer flow rate significantly increases that meaningful shooter’s-ear signature suppression performance gains are realized on the MK18. The reader is encouraged to examine the gas dynamics presented in the test data in all reviews of rifle silencers from HUXWRX / OSS for an example of the degree to which flow rate must increase.

As discussed in previous articles examining 30 caliber silencer performance on the 5.56x45mm MK18 weapon system, over-bore as a back pressure reducing mechanism is not nearly as efficient at increasing flow rate as is continuous gas routing through multiple flow paths. The same efficiency differential occurs between over-bore and reducing the severity of ejection port signature. This is one of the reasons why a threshold of diminishing returns may be realized on the MK18 at a Shooter’s Ear Suppression Rating of approximately 20, in Figure 5. Finally, this also highlights why the performance of silencers like the Surefire SOCOM556-RC2 (Review 6.52), CGS Helios QD, and KAC QDSS-NT4, may be considered outliers on the MK18. These three silencers demonstrate a combination of flow rate and muzzle signature that is unusually favorable for the shooter on this weapon system. Scaling of this phenomenon, as the 5.56x45mm barrel length increases, is a subject of further PEW Science research. In the current dataset, significantly increased flow rate achieved through multiple flow paths remains the most promising design element for hazard mitigation to the shooter, with muzzle signature still playing a mandatory role.

6.100.3 Review Summary: Dead Air Nomad-30 (1st Gen) on the MK18 5.56x45mm AR15 with 10.3-in Barrel

When paired with the 10.3-in barrel MK18 and fired with Federal XM193, the Dead Air Nomad-30 (1st Gen) mounted with the direct thread mount achieved a composite Suppression Rating™ of 27.9 in PEW Science testing. As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.

PEW Science Subjective Opinion:

The Dead Air Nomad-30 is a mid-size, relatively light weight, and relatively durable .30 rifle silencer. As a 5.56x45mm rifle silencer, it can be considered full-size, relative to dedicated models for the cartridge. The Nomad-30 has been refined since its 2018 release, and is also offered in an updated titanium version which reduces the weight of the system by over 4 ounces. Users should note that the supersonic suppression and back pressure characteristics of the Nomad-30 (1st Gen) highlighted in this review represent lower bound performance of the silencer. Nomad-Ti 5.56x45mm data and analysis publication by PEW Science is forthcoming.

The Nomad-30 contains broad and flattened stepped-cone baffles with ports utilizing an outer baffle annulus. Functionally, the design results in highly efficient management of supersonic flow by preventing a significant degree of high pressure stagnation in a way that does not significantly increase flow restriction. This balance of gas redistribution allows the Nomad technology to perform well with high pressure centerfire rifle cartridges but also excel at the suppression of lower pressure flow; the balance of which is atypical for a silencer of its length. Subsonic performance data of the Nomad-30 is the subject of future PEW Science publication. Note that the relative performance advantages of the Nomad-30 in the short barrel 5.56x45mm combustion regime are not as great as in the standard barrel 7.62x51mm regime. Nonetheless, its performance advantage over legacy Dead Air Sandman technology is significant across the board. On the MK18, the suppression performance of the Nomad-30 is extremely similar to that of the Q Trash Panda.

The rear mount threading of the Nomad series is 1.375”-24tpi; relatively common in today’s rifle silencer market. As a result of this common modular interface, a plethora of mounting systems may be used. The performance of the Nomad-30 may be influenced by mounting system choice. The user’s choice of mount may balance system weight, length, durability, utility, and even back pressure of the silencer. The data presented by PEW Science in this Sound Signature Review was measured with the direct-thread mount. The mount may be removed with included spanner tools from Dead Air; both the mount and the silencer body possess wrench indexing features. The silencer endcap is also removable; the use of endcaps with varying orifice diameter is possible, along with a recoil reducing so-called “E-Brake;” which is an endcap assembly that vents gas radially to counteract rifle recoil kinematics. PEW Science has not evaluated the efficacy of the E-brake system nor its influence on sound suppression performance with the Nomad-30.

The silencer is also offered in a titanium version, as stated above. The Ti version may be attractive to some users due to the weight reduction; PEW Science has tested the Ti version and noted moderately higher Suppression Rating performance than the steel version tested; this is due to the design improvements present in the Nomad-Ti since the Nomad-30 (1st Gen) release. Performance characteristics of newer Nomad-30 units are unknown to PEW Science, but are postulated to be improved over the 1st Gen. Detailed signature comparisons between the original steel and updated Ti versions of this silencer are the subject of future PEW Science research. Durability of the steel silencer is expected to be higher than that of the Ti silencer. PEW Science has not evaluated the durability of the Nomad silencer system(s) on semiautomatic or automatic host weapons.

In this review, the Nomad-30 performance metrics depend upon suppressing a supersonic centerfire rifle cartridge on a short barrel gas-operated rifle, which is an incredibly difficult task. PEW Science encourages the reader to remain vigilant with regard to all supersonic centerfire rifle suppression claims. The gas volume and combustion products created by the firing of the supersonic 5.56x45mm cartridge are significant; the measured pressure and impulse magnitudes, and their durations, illustrate this fact. Silencer performance on automatic (reciprocating) rifles depends on many factors. Weapon configuration may significantly influence total suppressed small arm system performance.

The hearing damage potential of supersonic centerfire rifle use is significant. PEW Science encourages the reader to consider the Suppression Rating when deciding on an appropriate silencer and host weapon combination for their desired use.