SSS.6.43 - Dead Air Nomad-30 (1st Gen) and the Savage Model 10 PC .308
/Dead Air Nomad-30 (1st Gen) on a Savage Model 10 .308 with 20-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 review contains single-test results using the Nomad-30 (1st Gen) mounted with the direct thread mount on the Savage Model 10 Precision Carbine rifle, chambered in .308WIN with a 20-inch barrel. Federal XM80C 149gr ammunition was used in the test.
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 both sound suppression and flow restriction (back pressure) 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 test data by PEW Science is forthcoming.
- Section 6.43.1 contains the Nomad-30 test results and analysis.
- Section 6.43.2 contains back pressure and Suppression Rating comparisons with selected compact to mid-size .30 rifle silencers possessing a PEW Science Back Pressure Metric, Ω [Pa-1] in Omega Zone 5 and below. Further information about the Ω metric and Omega Zones can be obtained in PEW Science Research Supplement 6.40 (Public Article).
- Section 6.43.3 contains the review summary and PEW Science opinions.
Summary: When paired with the Savage M10 20” .308 and fired with Federal XM80C, the Dead Air Nomad-30 (1st Gen) mounted with the direct thread mount achieved a Suppression Rating™ of 37.6 in PEW Science testing.
Relative Suppression Rating Performance is Summarized in SSS.7 - PEW Science Rankings
6.43.1 Dead Air Nomad-30 (1st Gen) Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the Nomad-30 is shown in Table 1. The data acquired 1.0 m (39.4 in) left of the muzzle is available for viewing to all. This is a members-only review and includes pressure and impulse waveforms measured at the shooter’s ear. PEW Science thanks you for your support; further testing, research, and development of PEW-SOFT and the Silencer Sound Standard is made possible by members like you!
Table 1. Dead Air Nomad-30 (1st Gen) Sound Metric Summary
6.43.1.1 SOUND SIGNATURES AT THE MUZZLE
Real sound pressure histories acquired with PEW-SOFT™ are shown below. 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.
Figure 1 shows a 1.2 millisecond long portion of the first round sound pressure signature of the Nomad-30 as measured 1.0 m left of the muzzle. There are five significant waveform features labeled:
The maximum amplitude of sound signature from internal weapon system combustion is measured to be 124.5 dB.
The endcap exit event results in an initial overpressure peak magnitude of 140.9 dB.
The first jet coupled with the endcap exit reaches 144.8 dB.
Secondary jetting continues and builds to an amplitude of 147.0 dB.
Peak FRP is reached at a maximum of 150.6 dB.
This is a somewhat typical sequence observed when firing supersonic .308WIN ammunition from a bolt-action rifle with an attached silencer that exhibits moderate flow restriction (back pressure); internal silencer design can significantly influence the measured timing and pressure amplitudes. Preliminary back pressure comparisons are shown in Section 6.43.2 of this review, with the PEW Science Back Pressure Metric, Ω [Pa-1].
Fig 1. Dead Air Nomad-30 (1st Gen) First Round Bolt Action Rifle Muzzle Sound Pressure Signature, 20-MAR-2021
The waveform shown in Figure 1 is fairly typical for silencers exhibiting flow restriction (back pressure) in PEW Science Omega Zone 5, such as the Rugged Surge in its Short Configuration (Review 6.22) and the SilencerCo Omega 300 (Review 6.10). Unsurprisingly, the computed predictive back pressure metric, Omega, for the Nomad-30 is bounded by that of those two silencers. It is important to note that the Nomad-Ti exhibits different performance characteristics, which is the subject of future PEW Science publication.
Characteristic early-time FRP waveform features of silencers with this gas flow behavior include an endcap exit event coupled with the first jet and a gradual building of secondary jetting primarily confined to the positive phase. Interestingly, the FRP signature of the Nomad-30 is significantly different than that of the CGS Hyperion K (Review 6.28); a silencer with a similar overall Suppression Rating on this platform, but a lower muzzle Suppression Rating. The Hyperion K vents gas with a higher mass flow rate than the Nomad-30; thus exhibiting lower back pressure. The severity of the sound signatures of the two silencers at the shooter’s ear on this weapon platform is similar.
An often cited silencer for comparison with the Nomad-30 is the Q Trash Panda (Review 6.4). The two silencers are significantly different in supersonic sound signature suppression and gas dynamics; this is a consequence of their radically different internal geometries. Despite being somewhat similar in overall exterior envelope and both being tubeless, the Trash Panda’s baffles are titanium straight ported cones with a generous bore. The Nomad-30 design possesses steel stepped-cone baffles with coaxial elements similar to elements of original SWR Omega geometry and elements of modern CGS Hyperion technology; the presence of which relieves localized high pressure stagnation and allows for more efficient supersonic gas flow suppression for a given silencer volume. Comprehensive Suppression Rating and back pressure comparisons with the Omega metric are provided in Section 6.43.2.
Closer views of the first peak of all shots (Fig 2a) and highest peak of the first shot (Fig 2b) are shown below. Figure 2a illustrates the consistency of the internal weapon system and silencer combustion events between all 5 shots during the test, followed by a consistent endcap exit event with immediately apparent influence of internal silencer atmosphere in the FRP waveform. The early time combustion event consistency in both amplitude and wave shape, from shot to shot, is discernable as a result of the high sample rate and raw, unfiltered data stream from PEW-SOFT. Figure 2b shows points later in time during Shot 1 as the maximum sound pressure occurs from the primary combustion event. Note that the total timescale in Figure 2a is 0.425 milliseconds (425 microseconds) and the total timescale in Figure 2b is only 0.1 milliseconds (100 microseconds). PEW-SOFT provides a sampling point every microsecond and the individual data points are shown in Figure 2b to illustrate this.
Fig 2a. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Muzzle Sound Pressure Early-Time Peaks, 20-MAR-2021
Fig 2b. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Muzzle Sound Pressure Shot 1 Peak, 20-MAR-2021
The primary sound signature pressure histories for all 5 shots with the Nomad-30 are shown in Figure 3a. The sound signatures of Shot 1, Shot 2, and Shot 3 are shown in Figure 3b, in early time. The real sound impulse (momentum transfer potential) histories from the same 5-shot test are shown in Figure 4a. In Figure 4b, a shorter timescale is shown comparing the impulse of Shot 1 to that of Shot 2 and Shot 3.
Fig 3a. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Muzzle Sound Pressure Signature, 20-MAR-2021
Fig 3b. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Muzzle Sound Pressure Signature, Short Time Window, 20-MAR-2021
Figure 4a. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Muzzle Sound Impulse Signature, 20-MAR-2021
Figure 4b. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Muzzle Sound Impulse Signature, Short Time Window, 20-MAR-2021
The Nomad-30 exhibits perceptible first round pop (FRP) at the muzzle on this platform; this is typical for silencers of its length and sound suppression performance. The FRP phenomenon is observable in the pressure regime, and it is clearly evident upon examination of the impulse waveforms in Figure 4 in both impulse rise time and slope. PEW Science inner ear modeling indicates FRP will be perceptible to bystanders and the shooter with the Nomad-30 on this host weapon platform.
The overall, muzzle, and ear Suppression Ratings for silencers tested by PEW Science, to date, can be compared directly using the tool in Section 7 of the Silencer Sound Standard - PEW Science Rankings and Section 6.43.2 of this review presents a comparison of Suppression Rating and back pressure for silencers of similar flow rate. Comprehensive silencer back pressure comparisons for .30 rifle silencers are available in PEW Science Public Research Supplement 6.40.
The Dead Air Nomad-30 (1st Gen) is quieter than the Dead Air Sandman-S (Review 6.11) at both the muzzle and ear on this weapon platform, while exhibiting higher back pressure (a higher Omega zone). Note that subsequent revisions of the Nomad-30 design possess different suppression and back pressure characteristics. However, the flow restriction (back pressure) of the Nomad-30 does not reach the low level of the Sandman-S; the Nomad design results in a lower mass flow rate (and significantly more sound signature suppression).
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 has made a concerted effort to characterize the FRP phenomenon with true physiological human inner-ear response analyses. Additional PEW Science Member Research Supplements containing this information are released periodically.
6.43.1.2 SOUND SIGNATURES AT SHOOTER’S EAR
Real sound pressure histories from the same 5-shot test of the Nomad-30 suppressor acquired with PEW-SOFT at the shooter’s ear are shown below. Again, 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 primary sound signature pressure histories at the ear for all 5 shots are shown in Figure 5. The primary sound signature history is shown on the left. A zoomed-in timescale is displayed on the right, in the region of peak sound pressure for Shot 1 and Shot 2. The real sound impulse (momentum transfer potential) histories at the ear from the same 5-shot test are shown in Figure 6. Again, full and short timescales are shown.
Figure 5a. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Ear Sound Pressure Signature, 20-MAR-2021
Figure 5b. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Ear Sound Pressure Signature, Short Time Window, 20-MAR-2021
Figure 6a. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Ear Sound Impulse Signature, 20-MAR-2021
Figure 6b. Dead Air Nomad-30 (1st Gen) Bolt Action Rifle Ear Sound Impulse Signature, Short Time Window, 20-MAR-2021
When examining the impulse waveforms measured at the shooter’s ear with the Nomad-30 (Figure 6), it exhibits less significant FRP in both the pressure and impulse regimes then at the muzzle. In PEW Science inner-ear modeling, there is still FRP noticeable to the shooter with the Nomad-30 on this platform. The peak pressure and impulse measured at the shooter’s head position are lower than several silencers in this class, however, the inner-ear response of the shooter is slightly more pronounced than with silencers exhibiting similar pressure amplitudes. PEW Science postulates this is due to mass flow rate duration and longer return of impulse amplitude to the negative phase at the shooter’s ear, when compared to the CGS Hyperion on this platform, for example.
PEW Science further postulates that higher mass flow rate (lower back pressure) silencers exhibiting similar measured impulse amplitudes at the shooter ear may sometimes result in lower inner ear response for a given waveform amplitude. More research is needed. PEW Science inner ear modeling comparisons of the Hyperion K and Nomad-30 (1st Gen) are forthcoming. The effect of positive phase waveform duration in impulse space, and the related correlation of low back pressure with shooter perception on bolt-action weapons, is not well studied and is also the subject of further PEW Science research.
6.43.2 Relative Suppression Rating and Back Pressure Comparisons (.30 Rifle Silencers)
The Dead Air Nomad-30 suppressor is intended to reduced flow restriction (back pressure) when compared to silencers of comparable small arm weapon system sound signature suppression. PEW Science has developed an empirical relation to quantify the back pressure (flow restriction) of silencers. Figure 7 shows supersonic suppression and back pressure comparisons between selected 7.62mm (30 caliber) rifle silencers shown in public PEW Science Sound Signature Reviews, as of the date of this review publication. The results shown in Figure 7 are calculated from real test data acquired with PEW-SOFT. Please note the following:
- The PEW Science Back Pressure Metric, Ω [Pa-1], may be generated for any silencer and suppressed weapon system using any suitable raw external overpressure signature data acquired 1.0 m left of the silencer endcap. PEW Science highly recommends data acquisition in accordance with The Silencer Sound Standard.
- Omega Zones are presented in Table 2, below, which are intended to provide guidance to weapons developers, silencer designers, and end-users, with regard to flow restriction characteristics of different silencer designs. It is very important to note that silencers possessing a relatively high Ω can still provide functional use on weapon systems. Some weapon systems are more sensitive to Ω than others.
- It is important to note that a silencer’s Omega Zone can shift when using a mounting scheme that differs from that used in the testing referenced in the published PEW Science Sound Signature Reviews. This phenomenon occurs due to some silencer mounting schemes significantly influencing flow restriction with some silencer designs.
- The theoretical lower limit of flow restriction, or so-called "zero back pressure" would be represented by the unsupressed state, Ω = 0 [Pa-1].
- PEW Science acknowledges that other dynamic events occur within a suppressed weapon system that can also influence weapon function. Therefore, PEW Science acknowledges that Ω is not the sole parameter one must consider for total supppressed weapon system operation. However, PEW Science postulates that the Ω metric influence can be significant.
Figure 7. Omega Back Pressure Metric And Suppression Rating Comparisons Of .308 Rifle Silencers Using PEW-SOFT Data and Analysis
Omega characterizes silencer back pressure. It is important to note that back pressure is not blow back. The back pressure of a silencer is the flow restriction it introduces to a suppressed weapon system. The blow back phenomenon that can occur during the use of a suppressed weapon system is caused by the reciprocating system actuating too early relative to overpressure decay within the weapon system, resulting in exposure of excessive internal system overpressure to atmosphere. Some weapons may be tuned to function well with silencers in a high Omega Zone. Some weapons may require low-Omega silencers due to constraints in their operating system(s). Omega metric technical details can be found in PEW Science Public Research Supplement 6.40.
Table 2. PEW Science Back Pressure Metric Omega Zones And Suppressed Weapon System Functional Descriptions
In Section 6.43.1.1, it was noted that the Nomad-30 exhibits waveform characteristics measured at the muzzle indicative of silencers possessing moderate flow restriction (moderate back pressure) in Omega Zone 5, such as the Rugged Surge in its short configuration and the SilencerCo Omega 300 with its ASR brake. Anecdotal user data indicates that the Nomad-30 has slightly lower back pressure than the SilencerCo Omega 300; the PEW Science Omega Back Pressure Metric does indicate this relative behavior. In addition to user choice of mounting scheme, a significant factor that may influence Nomad-30 flow characteristics is its baffle orientation during manufacturing. The Nomad-30 (1st Gen) tested by PEW Science for this Sound Signature Review possesses mill-cuts near each baffle center orifice that are offset radially; that is, the notches are not aligned as you view the bore axially. In addition to notch alignment, later iterations of Dead Air Nomad designs and unit assemblies may possess slightly larger bore aperture. These factors, along with mounting, all influence mass flow rate through the silencer, and therefore also influence back pressure. PEW Science postulates the Omega metric for the Nomad-30 shown in this review is an upper bound for users, but mounting schemes may influence the metric. Nonetheless, users should not expect the Nomad-30 or Nomad-Ti to reach the low back pressure of the Sandman-S.
The Dead Air Nomad-30 exhibits similar supersonic sound suppression performance as the larger Surefire SOCOM762-RC2 (Sound Signature Review 6.26) but at the expense of higher flow restriction. The different internal geometry of the Nomad results in differing subsonic performance. The Nomad-30 design represents a significant performance balance in the suppression of supersonic and subsonic flow, especially for its size. Future PEW Science Sound Signature Review publications will highlight these characteristics.
As stated in Section 6.43.1.1 the Dead Air Nomad-30 and Q Trash Panda perform significantly differently in supersonic sound signature suppression and gas dynamics; this is a consequence of their radically different internal geometries. The Trash Panda has a higher flow rate, and therefore lower back pressure, which lowers its supersonic suppression capability due to its simple ported straight-cone baffle design. In the subsonic performance regime, the performance gap between the Trash Panda and Nomad is reduced. This comparison is also the subject of future PEW Science Sound Signature Review publications.
Although it is very important that data in the supersonic flow regime not be extrapolated to the subsonic flow regime, silencers with certain internal characteristics like coaxial relief chambers can be designed to efficiently suppress sound signature in both; features used to relieve high pressure stagnation during supersonic flow can also be tailored to isolate subsonic flow propagation. The Dead Air Nomad, CGS Hyperion, and original SWR Omega technologies all possess characteristics that can form the foundation of well-rounded, balanced silencers with variable gas velocity suppression performance. The balancing of secondary and tertiary characteristics such as back pressure and flash, as well as durability and maintenance, provide further opportunities for silencer design advancements.
It bears repeating that peak sound pressure [dB], peak sound impulse [dB-ms], and Omega (Ω) [Pa-1], alone, do not determine the sound supression performance of a silencer. It is the combination of these and other waveform parameters that form the total sound signature and the influence on human inner ear response.
6.43.3 Review Summary: Dead Air Nomad-30 (1st Gen) on a Savage Model 10 .308 with 20-in Barrel
When paired with the Savage M10 20” .308 and fired with Federal XM80C, the Dead Air Nomad-30 (1st Gen) mounted with the direct thread mount achieved a Suppression Rating™ of 37.6 in PEW Science testing.
PEW Science Subjective Opinion:
The Dead Air Nomad-30 is a mid-size, relatively light weight, and relatively durable .30 rifle silencer that exhibits notable sound signature reduction for its size in the supersonic flow regime, while possessing a modular rear mount capability. 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 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.
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 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; no easy 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 .308WIN cartridge are significant; the measured pressure and impulse magnitudes, and their durations, illustrate this fact.
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.
