SSS.6.106 - Surefire SOCOM762-MINI2 and the Savage Model 10 PC .308
/Surefire SOCOM762-MINI2 on a Savage Model 10 .308 with 20-in Barrel
The SOCOM762-MINI2 is manufactured by Surefire. It is a 30 caliber centerfire rifle silencer, intended to suppress many cartridges with projectiles appropriately sized to travel through the bore, up to and including .300 Winchester Magnum. It has a 1.5-inch diameter and is 6.4 inches in length. The silencer mounts to the host firearm with a proprietary mounting system; the user may choose from various Surefire flash hider and muzzle brake mounts. The outer tube and end-cap are constructed of heat treated stainless steel. The baffles are constructed of Inconel steel alloy. As tested, the silencer weighs 16.6 ounces and the 3-prong flash hider weighs 4 ounces, for a total system weight of 20.6 ounces. The SOCOM762-MINI2 can be obtained from Silencer Shop.
This review contains single-test results using the SOCOM762-MINI2 with the SOCOM 3-Prong Flash Hider 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.
Caution: PEW Science urges caution when using the WARCOMP mount on this platform, for most users. Personal protective equipment (PPE), including eye and ear protection, is recommended for the operation of suppressed small arms, in general. For performance degradation details with the WARCOMP mount resulting from persistent high pressure gas leak phenomena, please reference the test reports for the Surefire SOCOM762-RC2 with 7.62x51mm ammunition (Review 6.26 and Review 6.73) and the Surefire SOCOM556-RC2 with 5.56x45mm ammunition (Review 6.52).
- Section 6.106.1 contains the SOCOM762-MINI2 test results and analysis.
- Section 6.106.2 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 6.106.3 contains the review summary and PEW Science opinions.
The Silencer Sound Standard is 3 Years Old! Happy Birthday!
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The Silencer Sound Standard is 3 Years Old! Happy Birthday! 〰️
Summary: When paired with the Savage M10 20” .308 and fired with Federal XM80, the Surefire SOCOM762-MINI2, mounted with the SOCOM 3-Prong Flash Hider mount, achieved a Suppression Rating™ of 25.1 in PEW Science testing. As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.
Relative Suppression Rating Performance is Summarized in SSS.7 - PEW Science Rankings
6.106.1 Surefire SOCOM762-MINI2 Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the SOCOM762-MINI2 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. Surefire SOCOM762-MINI2 Sound Metric Summary
6.106.1.1 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 SOCOM762-MIN2 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 3.
Fig 1a. Surefire SOCOM762-MINI2 Bolt Action Rifle Muzzle Sound Pressure Signature
Fig 1b. Surefire SOCOM762-MINI2 Bolt Action Rifle Muzzle Sound Pressure Signature, Short Time Window
Figure 2a. Surefire SOCOM762-MINI2 Bolt Action Rifle Muzzle Sound Impulse Signature
Figure 2b. Surefire SOCOM762-MINI2 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 Surefire SOCOM762-MIN2 as measured 1.0 m left of the muzzle. There are several significant waveform features labeled:
The end cap exit event results in an initial peak magnitude of 153.6 dB.
Primary jetting during the first shot occurs at an amplitude of 158.8 dB.
Secondary first shot jetting occurs at an amplitude of 153.8 dB, and decays to levels on the order of 146.3 dB.
The second shot possesses similar amplitudes of initial and primary jetting (150.9 db).
Pronounced jet-delay after the first shot is measured, and typical in all subsequent shots.
This is a somewhat typical sequence observed when firing supersonic .308WIN ammunition from a bolt-action rifle with an attached silencer that exhibits low flow restriction (back pressure). Internal silencer design can significantly influence the measured timing and pressure amplitudes. Preliminary back pressure comparisons are shown in Section 6.106.3 of this review, with the PEW Science Back Pressure Metric, Ω [Pa-1].
The waveforms shown in Figure 1 possesses early time characteristics very similar to the signatures from silencers exhibiting flow restriction (back pressure) in PEW Science Omega Zones 1 through 3. These silencers exhibit expedient high amplitude jetting in early time. Such silencers include the YHM Resonator K (Review 6.32), the HUXWRX (OSS) HX-QD 762 (Review 6.41), the short configuration of the Rugged Radiant (Review 6.12), the vented configuration of the CGS Helios QD (Review 6.13), the Griffin Armament Explorr 300 (Review 6.36), and the CGS Hyperion K (Review 6.28). Features of sound signatures in this flow regime are characterized by minimally decoupled bullet exit events with reduced post-exit amplitude suppression. This behavior is directly indicative of the low flow restriction of such silencers. Like the above silencers, the SOCOM762-MINI2 exhibits expedient high amplitude jetting on this platform.
PEW Science Research Note 1: The SOCOM762-MINI2 utilizes a similar internal design as other silencers in the Surefire SOCOM family such as the Surefire SOCOM762-RC2 (the full size version of the silencer, examined in Review 6.26 with the same ammunition) and the Surefire SOCOM556-RC2 (Review 6.52 on the 5.56x45mm MK18 platform). The SOCOM-RC and -MINI subfamilies of silencers utilize vented dished baffles along with early venting in the first expansion (blast) chamber; it is through these geometric attributes that the silencers exhibit relatively high flow rate for their design envelopes. However, the combustion pressure and duration from the 7.62x51mm cartridge is postulated to overwhelm this design if baffle quantity is significantly reduced. The Surefire SOCOM762-MINI2 is significantly louder than the SOCOM762-RC2 on this weapon platform. Although the SOCOM762-MINI2 is “optimized for 16-inch and longer barrels on 7.62mm rifles,” per the manufacturer, that optimization is postulated by PEW Science to be for length and weight, at the expense of suppression performance. The SOCOM762-MIN2 exhibits a PEW Science Suppression Rating at both the muzzle and shooter’s ear that is a category lower than the larger SOCOM762-RC2. Note that the flow rate of the MINI2 is also higher.
PEW Science Research Note 2: The SOCOM762-MIN2 exhibits first-round-pop (FRP) measured at the muzzle that is significantly perceptible to bystanders, in accordance with PEW Science inner ear modeling. The FRP is highlighted in both the pressure regime (Figure 1) and impulse regime (Figure 2). The jetting onset and impulse accumulation (gas momentum transfer potential measured in the free field) of the SOCOM762-MINI2 is extremely similar to the larger SOCOM762-RC2, albeit occurring at significantly higher amplitude. Similar step-function in the flow field post-FRP, characterized in the above signatures, can be compared with those in the full-size silencer dataset (ref. Fig 3b and Fig 4b, 6.26.1.1). It should be noted that the FRP from the full-size SOCOM762-RC2 on this platform, to bystanders, is still severe, despite its holistic suppression performance being higher than the SOCOM762-MINI2. The two silencers exhibit similar relative FRP performance.
Consistent with these measured pressure and impulse waveform features, the computed PEW Science Omega Metric is relatively low, placing the silencer in Omega Zone 2. Relative Suppression Rating and flow restriction (back pressure) data is presented in Section 6.106.2 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.
6.106.1.2 SOUND SIGNATURES AT SHOOTER’S EAR
Real sound pressure histories from the same 5-shot test of the SOCOM762-MINI2 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 3. 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 4. Again, full and short timescales are shown.
Figure 3a. Surefire SOCOM762-MINI2 Bolt Action Rifle Ear Sound Pressure Signature
Figure 3b. Surefire SOCOM762-MINI2 Bolt Action Rifle Ear Sound Pressure Signature, Short Time Window
Figure 4a. Surefire SOCOM762-MINI2 Bolt Action Rifle Ear Sound Impulse Signature
Figure 4b. Surefire SOCOM762-MINI2 Bolt Action Rifle Ear Sound Impulse Signature, Short Time Window
Like the larger Surefire SOCOM762-RC2, the SOCOM762-MINI2 exhibits less severe FRP at the shooter’s ear than at the weapon muzzle. Severe muzzle signature phenomena during the first shot are observable near the shooter’s head in the measured pressure history (after 30.25 ms, Fig 3b) and impulse history (Figure 4).
PEW Science Research Note 3: Note that the Surefire baffle design in the RC and MINI series requires a greater amount of baffles for sound suppression performance than some other designs, due to the degree of venting geometry present throughout the stack. This drop in suppression efficiency, as the silencer shortens, is common in such designs; the ancillary flow paths in the Surefire design occur early in the stack; the progressive nature of the venting is not limited to an isolated annular cavity. This more primitive venting design is postulated by PEW Science to exhibit significant performance limitations below a critical length envelope.
As typical, the overall sound signature measured at the shooter’s ear possesses significantly less amplitude in both the pressure and impulse regimes than the signature measured at the muzzle (refer to Table 1). Furthermore, the application of both pressure and impulse at the shooter’s ear is delayed when compared to the pressure and impulse at the weapon muzzle. The combination of varying amplitude and rise time to peak amplitude influences the response of the human ear.
It is extremely important to note that muzzle signature influences the signature to the weapon operator. This is a test on a bolt-action rifle. The same jetting phenomenon measured at the muzzle propagate toward the shooter (note the FRP peaks in Figure 3b). The standoff of the endcap to the shooter, as well as angle of incidence of the pressure (blast) waves, result in exponential decay of hearing damage risk when compared to personnel adjacent to the muzzle.
6.106.2 Relative Suppression Rating and Back Pressure Comparisons (.30 Rifle Silencers)
The SOCOM762-MINI2 suppressor is intended to offer moderate sound signature suppression in a compact envelope, while significantly reducing back pressure. 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:
- 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.
- 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.
- 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.
- 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.
Table 2. PEW Science Back Pressure Metric Omega Zones And Suppressed Weapon System Functional Descriptions
The Surefire SOCOM762-MINI2 possesses sound suppression performance on this platform, on average, that is similar to silencers such as the YHM Resonator K (Review 6.32), the vented configuration of the CGS Helios QD (Review 6.13), the Griffin Armament Explorr 300 (Review 6.36), the Rugged Razor762 (Review 6.16), and the Dead Air Sandman-K (Review 6.15). Most of these rifle silencers have high flow rates due to limited baffles, or specific high-flow design elements (internal baffle porting, endcap porting, or both).
PEW Science Research Note 4: It is interesting to note that the Surefire SOCOM762-MINI2 with the 3-Prong flash hider mount exhibits a lower bystander Suppression Rating than the SOCOM762-RC2, regardless of the mount used with the larger silencer, on this platform. However, for the weapon operator, the shooter’s ear Suppression Rating using the SOCOM762-MINI2 with the 3-prong flash hider is higher than with the SOCOM762-RC2 and the WARCOMP mount (Review 6.26). This illustrates the potentially severe consequences of WARCOMP mount use to signature suppression at the operator’s head. Even with a full-size silencer typically exhibiting a PEW Science Suppression Rating a category higher than the compact MINI2, the WARCOMP mount nullifies the operator suppression advantage and induces more hearing damage risk potential.
PEW Science has not tested the SOCOM762-MINI2 with the WARCOMP mount and considers the aforementioned testing and analysis of the WARCOMP mount on both 7.62x51mm and 5.56x45mm platforms sufficient, at this time. The issued caution of compromised suppressor performance to the operator with the WARCOMP family of mounts, with all Surefire rifle silencers, remains.
PEW Science Research Note 5: The Surefire SOCOM762-MINI2 is in Omega Zone 2 (Figure 6), which indicates that it exhibits relatively low flow restriction. Interior venting, coupled with shorter length and baffle count, contribute to this high flow rate. It is important to note that relatively high flow rate may be achieved in similar length envelopes, through the use of more advanced technologies. Such technologies include so-called flow through design from HUXWRX, Hyperion technology from CGS, and others.
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.
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.
6.106.3 Review Summary: Surefire SOCOM762-MINI2 on a Savage Model 10 .308 with 20-in Barrel
When paired with the Savage M10 20” .308 and fired with Federal XM80, the Surefire SOCOM762-MINI2, mounted with the SOCOM 3-Prong Flash Hider mount, achieved a Suppression Rating™ of 25.1 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 Surefire SOCOM762-MINI2 is a compact 30 caliber machine gun rated rifle silencer that possesses reduced sound signature suppression performance compared with many larger 7.62 silencers on the market, while possessing significantly reduced back pressure. The silencer may also be used on 5.56 weapon platforms; relative to dedicated 5.56 silencers, it may be considered full-size. PEW Science 5.56 testing and analysis results with the MINI2 are forthcoming.
The SOCOM762-MINI2 utilizes a similar internal design to other silencers in the Surefire SOCOM family such as the Surefire SOCOM762-RC2 (the full size version of the silencer) and the Surefire SOCOM556-RC2. The SOCOM-RC and -MINI subfamilies of silencers utilize vented dished baffles along with early venting in the first expansion (blast) chamber; it is through these geometric attributes that the silencers exhibit relatively high flow rate for their design envelopes. However, the combustion pressure and duration from the 7.62x51mm cartridge is postulated to overwhelm this design if baffle quantity is significantly reduced.
The Surefire SOCOM762-MINI2 is significantly louder than the SOCOM762-RC2 on this weapon platform. Although the SOCOM762-MINI2 is “optimized for 16-inch and longer barrels on 7.62mm rifles,” per the manufacturer, that optimization is postulated by PEW Science to be for length and weight, at the expense of suppression performance.
Only the SOCOM 3-Prong flash hider was used in the testing of this silencer. PEW Science has presented a significant amount of test data and analysis demonstrating the comprised suppression performance of the WARCOMP mount and increased hazards to the weapon operator. Surefire advises that the WARCOMP mount, while able to be used with the SOCOM762-MINI2, is intended for operators that are using their weapon unsuppressed and may use their silencer to suppress their weapon system infrequently. The WARCOMP provides an enhancement to shooting dynamics when unsuppressed, and these benefits are part of the intended design. Note that PEW Science has not performed an in-depth evaluation of the WARCOMP without a silencer mounted. For users that may only seldomly suppress their weapon system, the WARCOMP mount may offer benefits that make it an attractive choice.
The use of the Surefire locking collar is relatively straight forward. Note that some users have indicated carbon build-up on the mount that may prevent an operator from removing the silencer. Furthermore, carbon buildup may result in the silencer not being properly aligned upon reattaching; this misalignment may result in baffle strikes. PEW Science has experienced this in testing and highly recommends users of the Surefire mounting system clean their mounts regularly.
In this review, the SOCOM762-MINI2 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.
