SSS.6.113 - HUXWRX FLOW 762 Ti and the Savage Model 10 PC .308 (Free Version)

/

HUXWRX FLOW 762 Ti on a Savage Model 10 .308 with 20-in Barrel

The FLOW 762 Ti is designed and manufactured by HUXWRX. It is a 30 caliber centerfire rifle silencer, intended to suppress many cartridges with projectiles appropriately sized to travel through the bore, with no barrel length restrictions. It has a 1.8-inch diameter and is 6.75 inches long. The silencer mounts to proprietary HUXWRX LH-threaded taper-mount muzzle devices. With the muzzle device installed, the total length of the system is 6.9 inches. The entirety of the silencer is DMLS (3D-printed) Grade 5 Titanium. The silencer weighs 11.3 ounces and the Muzzle Brake-QD taper mount weighs 3.6 ounces, for a total system weight of 15 ounces, as tested. The FLOW 762 Ti can be obtained from Silencer Shop.

PEW Science is an independent private testing laboratory and also the world’s only publicly funded suppressed small arms research cooperative. Testing, data analysis, and reporting is generated with funding provided by PEW Science members. Any test data that is generated with any portion of private funding contains this disclosure. The testing and data production for this Sound Signature Review was funded in part by PEW Science Project PEW-HUX-054-001-23. Therefore, data pertaining to the FLOW 762 Ti in this Sound Signature Review is published with the express written permission of HUXWRX Safety Co. LLC.

This review contains single-test results using the FLOW 762 Ti with the Muzzle Brake-QD mount on the Savage Model 10 Precision Carbine rifle, chambered in .308WIN with a 20-inch barrel. Federal XM80 149gr ammunition was used in the tests.

  • Section 6.113.1 contains the FLOW 762 Ti test results and analysis.
  • Section 6.113.2 contains back pressure and Suppression Rating comparisons with selected .30 rifle silencers possessing a PEW Science Back Pressure Metric, Ω [Pa-1] in Omega Zone 4 and below. An updated Ω metric chart for the full suite of publicly evaluated .30 rifle silencers is also provided in this section. Further information about the Ω metric and Omega Zones can be obtained in PEW Science Research Supplement 6.40 (Public Article).
  • Section 6.113.3 contains detailed signature comparisons of the FLOW 762 Ti with those of the HX-QD 762 in this combustion regime (Members Only).
  • Section 6.113.4 contains the review summary and PEW Science opinions.

Summary: When paired with the Savage M10 20” .308 and fired with Federal XM80, the HUXWRX FLOW 762 Ti, mounted with the direct thread mount, achieved a Suppression Rating™ of 41.6 in PEW Science testing. As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.

The supersonic 5.56x45mm performance of the HUXWRX FLOW 762 Ti is detailed in Sound Signature Review 6.114, in which it achieved a Suppression Rating of 35.7.

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

6.113.1 HUXWRX FLOW 762 Ti Sound Signature Test Results

A summary of the principal Silencer Sound Standard performance metrics of the FLOW 762 Ti 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. HUXWRX FLOW 762 Ti Sound Metric Summary

 

6.113.1.1 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.

The primary sound signature pressure histories for all 5 shots with the FLOW 762 Ti 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 5-shot test are shown in Figure 2a. In Figure 2b, a shorter timescale is shown comparing the impulse of Shot 1 to that of Shot 2 and Shot 5.

Fig 1a. HUXWRX FLOW 762 Ti Bolt Action Rifle Muzzle Sound Pressure Signature

Fig 1b. HUXWRX FLOW 762 Ti Bolt Action Rifle Muzzle Sound Pressure Signature, Short Time Window

Figure 2a. HUXWRX FLOW 762 Ti Bolt Action Rifle Muzzle Sound Impulse Signature

Figure 2b. HUXWRX FLOW 762 Ti Bolt Action Rifle Muzzle Sound Impulse Signature, Short Time Window

Figure 1b shows a 2 millisecond long portion of the first round sound pressure signature of the HUXWRX FLOW 762 Ti as measured 1.0 m left of the muzzle. There are several significant waveform features labeled:

  1. Internal combustion within the silencer reaches a peak of 123.0 dB.

  2. The end cap exit event during the first shot, consisting of bullet shock and the initial jet, results in a peak overpressure magnitude of 150.9 dB.

  3. Peak first-round-pop (FRP) occurs with an amplitude of 152.0 dB. Secondary jetting continues (149.2 dB). Significant rarefaction occurs at an amplitude of 147.1 dB.

  4. The coupled exit event during the second shot reaches an amplitude of 145.4 dB; this shot peaks at 148.4 dB during secondary jetting.

This sequence of events is most often observed when firing supersonic .308WIN ammunition from a bolt-action rifle with an attached silencer that exhibits relatively low flow restriction (low back pressure). Internal silencer design can significantly influence the measured timing and pressure amplitudes. Preliminary back pressure comparisons are shown in Section 6.114.2 of this review, with the PEW Science Back Pressure Metric, Ω [Pa-1]. Note that weapon system influence is a function of both Ω and early-time wave propagation factors which may be measured inside the system, in close proximity to the muzzle orifice. These factors include the so-called PEW Science Alpha parameter; a subject of future research.

PEW Science Research Note 1: The reader may immediate compared the measured signatures from the HUXWRX FLOW 762 Ti on this host weapon to those measured from the HUXWRX (OSS) HX-QD 762 (6.41). The new generation FLOW 762 Ti possesses several similar signature features to that of the previous generation HX-QD 762 silencer, and also some key differences.

  1. Both silencers exhibit significant early-time positive phase jetting; however, the FLOW 762 Ti possesses a shorter positive phase duration during the initial jet.

  2. Both silencers exhibit defined FRP in both the pressure regime (Figure 1) and impulse regime (Figure 2).

  3. Both silencers exhibit increase impulse accumulation later in the shot string (Fig 2b); however, the FLOW 762 Ti continues to gain suppression efficiency, whereas the previous generation HX-QD 762 loses suppression efficiency as the shot string continues.

  4. While both silencers exhibit relatively expedient blow down (Fig 1a), the FLOW 762 Ti is measured to have a slightly lengthened blow down duration, relative to the HX-QD 762. The cavities within the FLOW series take more time for the gas to traverse.

Further detailed comparisons of the above phenomena, with supplementary waveform graphics, are included in Section 6.113.3 of this article, for PEW Science Members.

The HUXWRX FLOW 762 Ti, like the previously examined HUXWRX FLOW 556k (6.83), is significantly more advanced than the previous generation HX-QD series and contains an updated iteration of the HUXWRX Flow-Through technology.

PEW Science Research Note 2: As stated above, the FLOW 762 Ti is more advanced than the previous generation. The principal technical difference is its enhanced blow down time, facilitated by its more complex flow path geometry. By lengthening blow down time, but still maintaining a relatively high gross flow rate and low Alpha Parameter, the HUXWRX FLOW 762 Ti is able to offer higher suppression performance to both bystanders, and the weapon operator, on a bolt action weapon, than previous generation Flow-Through silencers. A greater degree of gas expansion, and heat transfer, both contribute to these performance increases. With regard to its increased efficacy to weapon operator hazard reduction, the sound field measured at that location is significantly less hazardous than that produced by the HX-QD 762 on this platform. More significant benefits to both the operator, and to bystanders, are realized on semiautomatic host weapons, as detailed in the test report of the HUXWRX FLOW 762 Ti on the 5.56x45mm MK18 (6.114).

PEW Science Research Note 3: The performance improvements gained with the FLOW technology from HUXWRX have reached a magnitude that result in bolt action weapon suppression that begins to meet or exceed that of traditional baffle technology, and in some cases, that of advanced baffle technology. Of particular note is the performance comparison of the HUXWRX FLOW 762 Ti to that of the Dead Air Nomad-Ti (6.44). Both silencers are titanium, both silencers are a similar length, and the FLOW 762 Ti provides equivalent hearing damage risk potential to the operator and bystanders on this weapon system, while producing a significantly higher flow rate. The Flow-Through technology from HUXWRX has now reached a point of efficacy that results in competitive performance across host types. For a silencer with the flow rate of the FLOW 762 Ti to achieve a PEW Science Suppression Rating in the 40-zone at the shooter’s ear on a centerfire bolt action rifle, is extremely notable. The FLOW 762 Ti also provides an equivalent level of protection to the weapon operator as a Q Thunder Chicken (6.20) on this host weapon; a conventional titanium silencer that is over 8 inches long with significantly higher back pressure.

PEW Science urges the reader not to misconstrue 7.62x51mm performance on a bolt action weapon system with that of subsonic 300 BLK bolt action performance. Each combustion regime, weapon system, and silencer combination possesses unique performance factors. PEW Science has not yet evaluated the FLOW 762 Ti in the subsonic 300 BLK combustion regime. Evaluation of the previous generation HX-QD 762 technology (6.45) in that regime displayed some performance limitations. Research is ongoing.

Consistent with these measured pressure and impulse waveform features, the computed PEW Science Omega Metric is relatively low, placing the silencer in Omega Zone 3. Relative Suppression Rating and flow restriction (back pressure) data is presented in Section 6.113.2 of this review.

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. Test results and analysis of the signature measured at the shooter’s ear is only available in the Member Version of this review.

6.113.2 Relative Suppression Rating and Back Pressure Comparisons (.30 Rifle Silencers)

The HUXWRX FLOW 762 Ti suppressor is intended to offer significant sound signature suppression with significant back pressure reduction. PEW Science has developed an empirical relation to quantify the back pressure (flow restriction) of silencers. Figure 5 and Figure 6 show 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 5 and Figure 6 are calculated from real test data acquired with PEW-SOFT. Please note the following:

  1. 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 end cap. PEW Science highly recommends data acquisition in accordance with The Silencer Sound Standard.
  1. Omega Zones are presented in Table 3, 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.
  1. 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.
  1. The theoretical lower limit of flow restriction, or so-called "zero back pressure" would be represented by the unsupressed state, Ω = 0 [Pa-1].
  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. Note that weapon system influence is also a function of early-time wave propagation factors which may be measured inside the system, in close proximity to the muzzle orifice. These factors include the so-called PEW Science Alpha parameter; a subject of future research.
  1. The Back Pressure Metric relations are most easily viewed on a logarithmic scale (See Figure 6).

Figure 5. Omega Back Pressure Metric And Suppression Rating Comparisons Of .308 Rifle Silencers Using PEW-SOFT Data and Analysis

As stated above, the PEW Science Back Pressure Metric is most easily viewed on a logarithmic scale. The metric is nonlinear; the shape of the trend in the data presented in Figure 6, below, illustrates the potential thresholds of extreme flow rate (approaching the unsuppressed state) and extreme flow restriction (approaching the trapping of the maximum amount of combustion byproducts in a system).

Figure 6. Omega Back Pressure Metric 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 in 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. Note that weapon system influence is also a function of early-time wave propagation factors which may be measured inside the system, in close proximity to the muzzle orifice. These factors include the so-called PEW Science Alpha parameter.

Table 2. PEW Science Back Pressure Metric Omega Zones And Suppressed Weapon System Functional Descriptions

The performance of the HUXWRX FLOW 762 Ti on this platform, holistically, is best compared with the Dead Air Nomad-Ti (6.44) and the Q Thunder Chicken (6.20), the former a high performance titanium silencer with advanced baffle technology that is similar in size, and the later a conventional titanium silencer that is over 8 inches long. The differing sizes, technologies, and back pressure of the three silencers represents a significant breadth in the Silencer Sound Standard Pedigree, and directly illustrates the potential of advanced manufacturing technologies when coupled with advanced internal design. The performance of the HUXWRX FLOW 762 Ti on a bolt action weapon system is the highest of any known Flow-Through silencer, available. Holistically, its performance is equivalent to that of the Nomad-Ti in level of protection to the operator and bystanders, on this weapon system.

PEW Science Research Note 7: In the analytical test report of the HX-QD 762 on this platform, it was noted that the HX-QD 762 represented one of the most significant performance outliers in PEW Science testing. The silencer exhibits significantly low back pressure (approaching the overall flow rate of the Dead Air Sandman-K) but with significantly higher sound suppression performance than the Sandman-K. Three other silencers were noted to exhibit similar “balanced” performance traits to the HX-QD 762:

  1. CGS Hyperion K (6.28)

  2. Dead Air Sandman-S (6.11)

  3. Surefire SOCOM762-RC2 (6.26)

The HX-QD 762, Hyperion K, Sandman-S, and SOCOM762-RC2 each posses radically different silencer designs with similar performance balance of low back pressure with moderate sound suppression on this host. The Hyperion K silencer achieves this balance through immediate venting to an outer annulus and generous bore. The Sandman-S addresses the issue with a generous bore and conventional baffle type. The SOCOM762-RC2 tackles the problem with aggressive venting. The HX-QD 762 uses helical ported elements to maintain flow, which is a key differentiator from the other silencers. Regardless of method, all four silencers are able to significantly reduce flow restriction (back pressure) and still keep their overall Suppression Rating above 30 on this host weapon platform. For this reason, PEW Science notes these silencers as significant performance outliers in the current 30 caliber silencer market. Notably, the HUXWRX FLOW 762 Ti eclipses the holistic suppression performance of them all, on this host weapon system.

PEW Science Research Note 8: The HUXWRX FLOW 762 Ti is in Omega Zone 3 (Figure 6), which indicates that it exhibits relatively low flow restriction. Continuous flow path geometry facilitates this higher flow rate.

PEW Science urges the reader not to misconstrue a low Omega metric with the mirroring of unsuppressed weapon function, nor a high Omega Metric with absolute use prohibition on semi-automatic systems. Each weapon system may experience varying sensitivity to different Omega Zones and users may exhibit varying preference for weapon system function and operability. The Zones are provided by PEW Science to assist the reader with determination of postulated applicability of silencer types, as some users may only have experience with certain silencers. The Omega Metric is one performance indicator; it allows overall flow rate phenomena to be categorized independently from sound signature suppression performance. Note that weapon system influence is also a function of early-time wave propagation factors which may be measured inside the system, in close proximity to the muzzle orifice.

It is extremely important to note 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. The PEW Science Suppression Rating computation considers all of these factors.

6.113.4 Review Summary: HUXWRX FLOW 762 Ti on a Savage Model 10 .308 with 20-in Barrel

When paired with the Savage M10 20” .308 and fired with Federal XM80, the HUXWRX FLOW 762 Ti, mounted with the direct thread mount, achieved a Suppression Rating™ of 41.6 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 HUXWRX FLOW 762 Ti is a relatively compact and lightweight 30 caliber machine gun rated rifle silencer that exhibits significant back pressure reduction and sound signature suppression performance, for its size. Its sound suppression performance at the shooter’s ear on a .308 bolt action rifle is competitive with that of advanced conventional baffle silencers. The silencer is constructed of 3D-printed Grade 5 Titanium and represents one of the most advanced systems evaluated by PEW Science, to date.

Like the previous generation HX-QD 762 series, the FLOW 762 Ti contains a series of ported helical baffle components within the silencer core. Functionally, the core uses geometric features to induce turbulent flow, while early and continuously routing combustion gasses into annular space for down-stream venting to atmosphere. The distal end of the silencer contains significant exit flow area around its outer circumference. The sound suppression efficiency of this design is directly proportional to cartridge pressure, flow velocity, and duration. The FLOW technology, taking advantage of additive manufacturing (3D-printing), is more advanced than that of the previous generation HX-QD series and the measured performance illustrates this advancement.

The sound suppression performance of the HUXWRX FLOW 762 Ti on a bolt action weapon is highly atypical for a silencer with such a high flow rate. Of particular note is the performance comparison of the FLOW 762 Ti to that of the Dead Air Nomad-Ti. Both silencers are titanium, both silencers are a similar length, and the FLOW 762 Ti provides equivalent hearing damage risk potential to the operator and bystanders on this weapon system, while producing a significantly higher flow rate. The Flow-Through technology from HUXWRX has now reached a point of efficacy that results in competitive performance across host types. For a silencer with the flow rate of the FLOW 762 Ti to achieve a PEW Science Suppression Rating in the 40-zone at the shooter’s ear on a centerfire bolt action rifle, is extremely notable. The FLOW 762 Ti also provides an equivalent level of protection to the weapon operator as a Q Thunder Chicken on this host weapon; a conventional titanium silencer that is over 8 inches long with significantly higher back pressure.

The aforementioned method by which the FLOW 762 Ti shapes gas flow and allows it to exit the silencer is significantly different than many silencers on the current market. As shown in previous PEW Science reviews of the HX-QD 762, the flow characteristics of the silencer significantly reduce efficiency in the subsonic flow regime when compared to the supersonic flow regime. PEW Science has not yet evaluated the FLOW 762 Ti with subsonic 300 BLK.

As was noted in the evaluation of the FLOW 556K, the FLOW technology continues to represent the best balance of Suppression Rating and back pressure reduction in the supersonic flow regime measured by PEW Science.

One consequence of high mass flow rate through a silencer is a potential increase in flash signature. However, the FLOW series silencers possesses flash-hiding features on their endcaps and increased internal surface roughness through additive manufacturing, compared with the previous generation HX-QD series. PEW Science postulates that these design factors influence flash suppression performance, but has not yet evaluated the flash hiding performance of the FLOW 762 Ti. Qualitative measurements of flash using the FLOW 556K on short barrel 5.56x45mm weapons has indicated adequate flash suppression for the author.

The left-hand (LH) threaded taper mounts from HUXWRX are simple to operate. They may be installed on the weapon system with an adjustable wrench; the mount bodies, themselves, serve as wrench-flats. Newer iterations of the mounts may include additional wrench flat features. As the silencer is LH threaded to the mount, the mount is easily removed from the silencer, should the mount be detached from the weapon while still in the silencer. One can then tighten the entire assembly to the conventionally right-hand (RH) threaded barrel muzzle, and continued RH tightening will subsequently loosen the silencer from the mount. Although proper mount installation torque mitigates such a solution from being absolutely necessary, this mechanical feature is welcome for practicality. The distal vents of the silencer produce thrust which actively tighten the silencer to the mount, during use. This feature is unique to HUXWRX rifle silencers; PEW Science confirms that this feature demonstrates efficacy in the field.

PEW Science has not evaluated the durability of the FLOW silencer system(s) on semiautomatic or automatic host weapons. Note that the nature of low flow restriction (low back pressure) silencers may positively influence durability, as the silencers are designed to vent more quickly than traditional designs, relative to the time regime of combustion. As the FLOW 762 Ti is 3D-printed in its entirety, PEW Science postulates that it may exhibit increased durability when compared to the previous HX-QD generation. These phenomena are subjects of further research. HUXWRX reports this postulation to be correct, in accordance with their internal testing.

In this review, the FLOW 762 Ti 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.