SSS.6.208 - SilencerCo Sparrow and the Beretta 21A (Free Version)
/SilencerCo Sparrow on a Beretta 21A Subcompact Semiautomatic Pistol
The Sparrow is designed by SilencerCo. It is a full-size 22 caliber rimfire silencer, intended to suppress cartridges ranging from .22LR to 5.7x28mm. It has a 1.07-inch outer diameter and is 5.08 inches long. The entirety of the silencer is constructed from stainless steel; the outer tube captures a monolithic baffle core (“monocore”) with two “clam shell” liners that facilitate ease of user disassembly for maintenance. The silencer may be installed on host weapons threaded 1/2-28-tpi and weighs 6.5 ounces, as tested. The Sparrow can be obtained from Silencer Shop.
Report Table of Contents:
6.208.1 SilencerCo Sparrow test results and analysis.
6.208.2 Suppression Rating comparisons with selected .22 rimfire silencers in the subsonic ammunition combustion regime.
6.208.3 Report summary and PEW Science laboratory staff technical opinions.
Silencer Hazard Map:
The predicted personnel hazards generated by the tested weapon system in this report, in the free field, are shown in the adjacent animated Silencer Hazard Map. Click or tap the Map to enlarge. The image animation cycles between First Shot hazards and Average hazards. Please reference Silencer Hazard Map Brief 8.1.6 for further details. The PEW-SOFT HD Blast Hazard Prediction Tool and Hazard Mapper is presented in Report 8.1.1.
SilencerCo Sparrow Beretta 21A .22LR Free Field Animated Silencer Hazard Map Produced by PEW-SOFT HD Blast Hazard Prediction Tool using PEW Science Test Data
Historical Note: The SilencerCo Sparrow is considered historically significant in that it was the first and only product launched by SilencerCo at their inception in 2008, has proliferated widely, and is still in production. The relatively simple monocore has engineered roots from a well known designer who benevolently participated in the public silencer enthusiast discussion forum Silencer Talk. The community is also historically significant as many designers, past and current, participated by sharing ideas and support with the professional and consumer public. At the time, many rimfire silencers were not user serviceable, and if they were, they were exceedingly difficult to disassemble for cleaning after heavy use. SilencerCo launched the Sparrow formally as its only product and reception was immediately warm and welcoming among the enthusiast community; the design utility was recognized. Over the years, as silencer taboo in the firearms community decreased, government regulatory processes became more streamlined, and the silencer market expanded, the Sparrow introduced a large number of shooters to small arm weapon system suppression. It is our hope that the performance showcased herein assists the public with relative comparisons using high fidelity data and analysis, almost two decades later. (continued in report body)
This Sound Signature Review contains single-test results using the SilencerCo Sparrow mounted to the Beretta 21A subcompact semiautomatic pistol, chambered in .22LR with a 2.4-inch barrel. CCI Standard Velocity 40gr ammunition was used in the test.
Summary: When paired with the Beretta 21A subcompact semiautomatic pistol and fired with CCI SV .22 LR ammunition, the SilencerCo Sparrow achieved a composite Suppression Rating™ of 74.5 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.
6.208.1 SilencerCo Sparrow Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the SilencerCo Sparrow 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 public PEW Science testing, research, and development with a membership, here. State-of-the-art public firearm sound signature testing and research conducted by PEW Science is supported by readers like you.
Table 1. SilencerCo Sparrow Sound Metric Summary
6.205.1.1 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 and the weapon was fired until the magazine was empty; the Beretta 21A pistol does not possess a last round bolt hold open feature, and thus the slide does not lock back on the last round fired. Only five shots are considered in the analysis, to maintain consistency with the overall PEW Science public dataset. The waveforms are not averaged, decimated, or filtered. The data acquisition rate used in all PEW Science laboratory sound signature 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 laboratory testing; the recognized 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 are shown in Figure 1a. A zoomed-in timescale displays the region of peak sound pressure in Figure 1b, of the first two shots. The real sound impulse (momentum transfer potential) histories from the same 6-shot test are shown in Figure 2. Again, full and short timescales are shown, this time of Shots 1, 2, and 3.
Fig 1a. SilencerCo Sparrow Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Pressure Signature
Fig 1b. SilencerCo Sparrow Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Pressure Signature, Short Time Window
Figure 2a. SilencerCo Sparrow Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Impulse Signature
Figure 2b. SilencerCo Sparrow Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Impulse Signature
The SilencerCo Sparrow is historically significant. Please see the Historical Note at the beginning of this report.
Historical Note (Continued): The Sparrow is a full-size rimfire silencer; its design originated during a time when rimfire silencer popularity was increasing and as such, so was real use. When rimfire silencers are heavily fired, super heating of the bases of unjacketed projectiles deposit lead condensate throughout the internals. Chemical cleaning of rimfire silencers in a relatively nonhazardous fashion was not as well understood in the silencer community at the time, and such cleaning methodology can have some limitations depending on the amount of lead buildup. Even if user serviceable, cores or baffles can become seized to the outer tube. “Pusher tools” exist for many legacy rimfire silencers as a disassembly solution (AAC, SWR, Liberty Suppressors, and others). SilencerCo’s solution to remedy this employed two inner “clam shells” surrounding the SilencerCo Sparrow’s monocore that isolate the inner surface of the tube from lead condensate. Upon outer tube removal, the clam shells can be separated from the core mechanically, and cleaning of the core can be completed by a method of the user’s choosing.
PEW Science Research Note 1: The performance of the SilencerCo Sparrow, like all silencers, has several nuances. It is important to note that suppressing long(er) barrel rimfire weapons is relatively easily accomplished by most modern rimfire silencers and many aspects of a silencer’s suppression performance are not revealed on such platforms. When attempting to suppress short barrel small arm weapon systems, a silencer’s true suppression potential can be examined. This is the case from rimfire to magnum rifle cartridges, and everything in between. Performance does not always scale proportionally with barrel length, as has been discussed in Silencer Sound Standard research ad nauseum. However, at the very least, the high blast load input pressures and impulses from short barrels fully exercise a silencer’s core and unburnt propellant load challenges even the most advanced first-round-pop (FRP) quenching mechanisms.
The above measured test data demonstrates a well known attribute of the SilencerCo Sparrow: its FRP on short barrels. Please note the following observed phenomena:
Relatively typical blast pressure onsets and durations, along with unremarkable weapon kinematics (Fig. 1a).
Significant and severe FRP blast jetting with early development. After initial precursor jetting which is coincident from shot to shot, multiple FRP jet phases develop. This sequential and severe FRP propagation is characterized in pressure space (Fig. 1b) and impulse space (Fig. 2).
Post-FRP consistency in early time is robust. Secondary post-FRP accumulation in later time presents in some shots and is otherwise not significant (Fig. 2b).
PEW Science Research Note 2: The FRP signature severity from the SilencerCo Sparrow, to bystanders, is almost an order of magnitude more severe than subsequent shots on the test host weapon, on average. This hazard severity should be considered extremely significant by modern rimfire suppression standards. The animated Silencer Hazard Map at the beginning of this report illustrates this differential visually. Note that the Suppression Rating is a full category higher to personnel adjacent to the weapon system, on average, than it is during the first shot. Any personnel firing the weapon or in the general area will immediate recognize the first shot as more severe when suppressing a short barrel rimfire weapon with the SilencerCo Sparrow. This definitive conclusion has been well known in the silencer community for almost two decades anecdotally, and is quantitatively supported by the instrumented blast testing and analysis in this report.
The SilencerCo Sparrow is nominally over 5-inches long. Equal to or below the strict 5-in length cutoff, three shorter rimfire silencers evaluated on the same short barrel semiautomatic pistol in the research pedigree exist:
The Sparrow outperforms the short configuration of the Oculus, as one would expect. However, both the CAT BEN and Off Grid Suppressors Scorpius outperform the SilencerCo Sparrow in bystander hazard reduction by over a full Suppression Rating category. The performance differential between these modern designs and the Sparrow design is nontrivial. It is important to note that the published calculated Suppression Ratings are average values. When considering the aforementioned severe FRP signature from the Sparrow, the performance differential between it and other models is even greater. The relatively simple and generously chambered monocore has limited FRP quenching mechanisms. Propagation of ancillary combustion occurs unimpeded during the first shot and is significantly exacerbated by the higher pressures and unburnt powder load of a short barrel.
PEW Science Research Note 3: On average, while the muzzle Suppression Rating of the SilencerCo Sparrow is lacking for its size, its shooter’s ear Suppression Rating on this host weapon is relatively competitive with modern designs. After FRP, the somewhat serendipitous nature of ejection port blast hazards help lower the relative operator severity of the Sparrow when compared to some of its peers. This phenomenon results in many users anecdotally enjoying the use of the Sparrow as operators in the free field with this type of host weapon, FRP notwithstanding. Note that FRP severity on longer barrels will be less severe with the SilencerCo Sparrow, as is the case with many rimfire silencers in general.
PEW Science Research Note 4: The rimfire silencer short-barrel pistol suppression performance Rankings are now expanding; the SilencerCo Sparrow joins the CAT BEN, the PWS BDE 22, the Off Grid Scorpius, the Otter Creek Labs Titanium, the CAT SR, the Resilient Suppressor’s Jessie’s Girl and the Rugged Oculus (in two configurations) in the current published dataset. Again, users should note that performance of rimfire silencers on long and short barrels may be significantly different, even with subsonic ammunition, depending on silencer design. These performance differentials are the subject of ongoing PEW Science research.
The signatures measured and analyzed at the shooter’s ear are presented in the full Member Version of this report.
Gross hazards and behaviors of the SilencerCo Sparrow on the subcompact Beretta 21A rimfire pistol are compared with those of other silencers in the following section.
6.208.2 Suppression Rating Comparison - Semiautomatic Subsonic .22 LR
The SilencerCo Sparrow was developed almost a decade ago to maximize pure sound signature reduction (PEW Science Suppression Rating) in an easy to maintain package. Figure 5 shows a performance comparison of rimfire silencer configurations tested on a subcompact semiautomatic pistol shown in public PEW Science testing, to date. Suppression Ratings are shown for both the shooter and bystanders.
Figure 5. Suppression Rating Comparisons Of Rimfire Silencers Using PEW-SOFT subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Test Data
The performance of the SilencerCo Sparrow on the short-barrel subcompact semiautomatic rimfire pistol platform is relatively competitive with silencers on the current market, on average, when considering the hazard reduction to the operator. When considering the hazard reduction to bystanders (personnel adjacent to the weapon system), its performance is less robust. This is largely driven by its aforementioned significant FRP. Please reference the animated Silencer Hazard Map at the beginning of this report and in Silencer Hazard Map Brief 8.1.6.
At the shooter’s ear, the hazard reduction from the Sparrow is similar to that of the Otter Creek Labs Titanium on this weapon platform, on average. At the muzzle (to bystanders), the hazard reduction from the SilencerCo Sparrow is lower than most full size silencers. This will result in user impressions of the Sparrow being “louder” than other rimfire silencers when shot on a pistol, in many environments.
The primary reason(s) for the Sparrow’s performance differential from its modern peers is not necessarily that it possesses a monocore. On the contrary, the PWS BDE 22 (6.190) also possesses a relatively conventional monocore, and is one of the highest performing rimfire silencers tested on this platform. The Sparrow’s performance suffers due to the specific geometry used in its core; it performs well with inert atmosphere, but FRP quenching is poor. Brute force FRP suppression from additional baffle elements or more advanced geometry, or both, would be required to mitigate this performance shortfall.
The signature of a high performance rimfire silencer with subsonic ammunition fired from a semiautomatic pistol is significantly suppressed and may not sound like a “gunshot” to the operator or to bystanders. When such systems enter the 70-zone on the Suppression Rating scale on a reciprocating weapon, the signatures have a large proportion of audibly discernable mechanical noise. It is important for operators and bystanders to remain cognizant of the potential hazards of firearm use and the potential lethality of such weapon systems; the operation of such systems, if not in accordance with weapon and silencer manufacturer instructions, may still result in serious injury or death. The user is encouraged to be mindful of the degree to which sound signature suppression, and resulting personnel hazards, can vary across designs. Small arm weapon system suppression performance is a spectrum. The PEW Science Suppression Rating and the Silencer Sound Standard help quantify this spectrum for end users and industry, objectively.
6.208.3 Review Summary: SilencerCo Sparrow on a Beretta 21A Subcompact Semiautomatic Pistol
When paired with the Beretta 21A subcompact semiautomatic pistol and fired with CCI SV .22 LR ammunition, the SilencerCo Sparrow achieved a composite Suppression Rating™ of 74.5 in PEW Science testing.
As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.
PEW Science Laboratory Staff Opinion:
The SilencerCo Sparrow is a full-size rimfire silencer that exhibits relatively competitive performance, on average, to modern designs. However, its first-round-pop (FRP) suppression performance on short barrel weapons is significantly lacking. A key feature of the Sparrow is its ease of disassembly for user maintenance. Debuted as SilencerCo’s first product almost two decades ago, the Sparrow possesses internal clam shells that isolate the outer tube from the monolithic baffle core. The silencer is rated for most rimfire cartridges as well as 5.7x28mm, and has enjoyed significant proliferation throughout the market.
The Sparrow’s design originated during a time when rimfire silencer popularity was increasing and as such, so was real use. When rimfire silencers are heavily fired, super heating of the bases of unjacketed projectiles deposit lead condensate throughout the internals. Chemical cleaning of rimfire silencers in a relatively nonhazardous fashion was not as well understood in the silencer community at the time, and such cleaning methodology can have some limitations depending on the amount of lead buildup. Even if user serviceable, cores or baffles can become seized to the outer tube. “Pusher tools” exist for many legacy rimfire silencers as a disassembly solution (AAC, SWR, Liberty Suppressors, and others). SilencerCo’s solution to remedy this employed two inner “clam shells” surrounding the SilencerCo Sparrow’s monocore that isolate the inner surface of the tube from lead condensate. Upon outer tube removal, the clam shells can be separated from the core mechanically, and cleaning of the core can be completed by a method of the user’s choosing.
The performance of the SilencerCo Sparrow, like most silencers, has several nuances. It is important to note that suppressing long(er) barrel rimfire weapons is relatively easily accomplished by most modern rimfire silencers and many aspects of a silencer’s suppression performance are not revealed on such platforms. When attempting to suppress short barrel small arm weapon systems, a silencer’s true suppression potential can be examined. The FRP signature severity from the SilencerCo Sparrow, to bystanders, is almost an order of magnitude more severe than subsequent shots on the test host weapon, on average. This hazard severity should be considered extremely significant by modern rimfire suppression standards. The animated Silencer Hazard Map at the beginning of this report illustrates this differential visually. Note that the Suppression Rating is a full category higher to personnel adjacent to the weapon system, on average, than during the first shot. Any personnel firing the weapon or in the general area will immediate recognize the first shot as more severe when suppressing a short barrel rimfire weapon with the SilencerCo Sparrow. This definitive conclusion has been well known in the silencer community for almost two decades, and is supported by the instrumented blast testing and analysis in this report.
On average, while the muzzle Suppression Rating of the SilencerCo Sparrow is lacking for its size, its shooter’s ear Suppression Rating on this host weapon is relatively competitive with modern designs. After FRP, the somewhat serendipitous nature of ejection port blast hazards help lower the relative operator severity of the Sparrow when compared to some of its peers. This phenomenon results in many users anecdotally enjoying the use of the Sparrow as operators in the free field with this type of host weapon, FRP notwithstanding. Note that FRP severity on longer barrels will be less severe with the SilencerCo Sparrow, as is the case with many rimfire silencers in general.
The primary reason(s) for the Sparrow’s performance differential from its modern peers is not necessarily that it possesses a monocore. On the contrary, the PWS BDE 22 also possesses a relatively conventional monocore, and is one of the highest performing rimfire silencers tested on this platform. The Sparrow’s performance suffers due to the specific geometry used in its core; it performs well with inert atmosphere, but FRP quenching is poor. Brute force FRP suppression from additional baffle elements or more advanced geometry, or both, would be required to mitigate this performance shortfall.
PEW Science has not evaluated the durability of the SilencerCo Sparrow, nor its performance on cartridges other than subsonic .22 LR. It is important for the user to contact the manufacturer to determine the suitability of firing schedules and use cases.
In this review, the SilencerCo Sparrow performance metrics depend upon suppressing a subsonic rimfire cartridge on a subcompact semiautomatic rimfire pistol, which is a difficult task. While the sound signature of such systems can be suppressed to levels that may not sound like a “gunshot” to the operator or to bystanders, PEW Science encourages the reader to remain vigilant with regard to all subsonic rimfire cartridge suppression claims. It is important for operators and bystanders to remain cognizant of the potential hazards of firearm use and the potential lethality of such weapon systems; the operation of such systems, if not in accordance with weapon and silencer manufacturer instructions, may still result in serious injury or death.
The hazard potential of subsonic rimfire pistol use is not insignificant. PEW Science encourages the reader to consider the Suppression Rating when deciding on an appropriate silencer and host weapon combination for their desired use.
