SSS.6.150 - Otter Creek Labs Titanium and the Beretta 21A
/Otter Creek Labs Titanium on a Beretta 21A Subcompact Semiautomatic Pistol
The Titanium is designed by Otter Creek Labs. It is a compact and lightweight 22 caliber rimfire silencer, intended to suppress cartridges ranging from .22LR to 5.7x28mm. It is approximately 1.1 inches in diameter and is 5.2 inches long. The silencer tube, mount, end cap, and baffle assembly are constructed entirely of titanium. The silencer is able to be disassembled and may be installed on host weapons threaded 1/2”-28tpi. The silencer weighs 4.1 ounces, as tested. The Titanium can be obtained from Silencer Shop.
PEW Science is an independent private testing laboratory and also hosts the world’s only independent public suppressed small arms research cooperative. Testing, data analysis, and reporting for public research 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 white paper was funded in part by PEW Science Project PEW-OCL-073-001-23. Therefore, data pertaining to the Titanium in this Sound Signature Review is published with the express written permission of Otter Creek Labs.
This Sound Signature Review contains single-test results using the Otter Creek Labs Titanium 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.
Section 6.150.1 contains the Otter Creek Labs Titanium test results and analysis.
Section 6.150.2 contains Suppression Rating comparisons with selected .22 rimfire silencers in the subsonic cartridge regime.
Section 6.150.3 contains the review summary and PEW Science laboratory staff technical opinions.
Summary: When paired with the Beretta 21A subcompact semiautomatic pistol and fired with CCI SV .22 LR ammunition, the Otter Creek Labs Titanium achieved a composite Suppression Rating™ of 82.8 in PEW Science testing.
The bolt-action rifle rimfire performance of the Otter Creek Labs Titanium is detailed in Sound Signature Review 6.149, in which it achieved a composite Suppression Rating of 91.4.
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
6.150.1 Otter Creek Labs Titanium Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the Otter Creek Labs Titanium 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. Otter Creek Labs Titanium Sound Metric Summary
6.150.1.1 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 bold 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, 4, and 5.
Fig 1a. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Pressure Signature
Fig 1b. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Pressure Signature, Short Time Window
Figure 2a. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Impulse Signature
Figure 2b. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Muzzle Sound Impulse Signature
The Otter Creek Labs Titanium is a lightweight and relatively compact rimfire silencer. The Titanium uses a somewhat conventional baffle design, and includes some design features allowing it to achieve high performance with the higher input pressures of short barrels. Low-pressure host weapon performance of the Titanium is addressed in test report 6.149 with the 16-in barrel CZ 452 .22LR bolt-action rifle. In that test, although the silencer exhibited lower performance than some other models, the Titanium was shown to produce competitive performance with low-pressure optimized silencers such as the Rugged Oculus (6.1), demonstrating extremely consistent gas dynamics and minimal to no first-round-pop (FRP).
This test was performed with the subcompact semiautomatic Beretta 21A pistol. There are several signature features of note in the measured data:
Relatively low amplitude free field pressure during primary blowdown (Fig. 1a).
Early-time FRP divergence with relatively expedient flow normalization, post-peak (Fig. 1b and Fig. 2a).
Relatively consistent impulse accumulation after FRP, with limited but measurable acceleration of accumulation later in the string (Fig. 2b).
The above measured performance attributes indicate that the Otter Creek Labs Titanium likely exhibits more optimized suppression performance with shorter barrel high-pressure rimfire hosts.
PEW Science Research Note 1: The measured FRP signature from the Titanium is relatively unique in that it does exhibit significant early-time divergence, but quickly returns to normalized baseline prior to the time regime at which peak distal flow is reached in subsequent shots. This behavior contributes to a high degree of FRP severity masking with the silencer on this host weapon platform. The Otter Creek Labs Titanium does produce measurable and noticeable FRP on a rimfire pistol, but just like it demonstrated on a bolt-action rifle, the FRP signature from the Titanium is postulated to exhibit only minimal severity differential relative to subsequent shots. Both the Rugged Oculus (6.2) and Resilient Suppressors Jessie’s Girl (1.36) are unable to achieve this type of FRP masking on this host weapon. It is important to note that this mechanism is not unique to rimfire suppression; this type of FRP signature severity masking also occurs in other combustion regimes on completely different weapon systems and with completely different silencers in the free field, such as with the Thunder Beast ULTRA 9 (6.24) and the long configuration of the Rugged Surge (6.22) fired on .308 bolt-action platforms.
PEW Science Research Note 2: The consistency of the Otter Creek Labs Titanium signatures, post-FRP, is notable. However, as discussed in (3) above, the silencer does demonstrate measurable accelerated impulse accumulation later in the shot string; a direct result of system heating lowering efficiency. Within the scope of this test program and the pressure amplitude and time regimes of .22LR combustion, PEW Science postulates that the overall behavior of the Titanium on this host type is only nominally influenced by this phenomenon. Users should experience, for all intents and purposes, consistent free field suppression performance from the Titanium on semiautomatic rimfire pistols.
PEW Science Research Note 3: The Otter Creek Labs Titanium is classified as a conventional design in the PEW Science taxonomy. However, there are simple geometric features of its design that allow it to demonstrate the aforementioned high-pressure performance optimization. As previously discussed in the bolt-action test report, like the aforementioned low-pressure-optimized Rugged Oculus, the Otter Creek Labs Titanium uses traditional baffle geometry with a curved cone component. However, the proportion of frontal baffle surface area and curvature in the Titanium is greater; this geometric change, coupled with it’s two notches and deeper overall throat and extra baffle, allow the Titanium to almost mimic the gas dynamics of the Oculus on a bolt-action rifle, while exceeding the performance of the Oculus on the shorter barrel high-pressure Beretta 21A. As high performance with low-pressure bolt-actions is relatively commonplace, a silencer design that is able to excel with higher pressures and still compete in the lower pressure regime is notable. PEW Science postulates that the deeper overall throat provides a volumetric gas expansion advantage for stagnation relief, fed by adequate notch jetting in the time regime of higher pressure combustion, allowing the the Titanium to significantly outperform the Oculus on a short barrel pistol. For conventional systems of similar size, this nuanced design variation is of significant note.
PEW Science Research Note 4: The Otter Creek Labs Titanium is not a low-backpressure system, nor is it a significantly advanced design. As a result, the overall pressure field produced by the system approaches limits of the size envelope; its high-pressure optimization discussed above notwithstanding. Therefore, the operator hazard reduction potential when using the Titanium on a rimfire pistol is largely driven by its exceptional muzzle suppression. As backpressure becomes a greater factor for a suppressed rimfire pistol system, shooter hazard with the Titanium may increase accordingly. This type of performance differential is measurable and there is precedent for it in the research pedigree in the examination of the test program results for the CAT SR on the Beretta 21A (6.141). The CAT SR, with an implementation of SURGE BYPASS technology to reduce system backpressure, is significantly more advanced. The requisite early-time flow rate increases to achieve such performance, combined with late-time gas momentum throttling to maintain high pressure field suppression, are seldom present in silencer designs, in general, let alone rimfire silencer designs. Excluding these advancements, the Otter Creek Labs Titanium demonstrates some of the highest rimfire pistol suppression performance for a conventional baffle design in the research pedigree, to date.
PEW Science Research Note 5: The rimfire silencer short-barrel pistol suppression performance Rankings are now expanding; the Otter Creek Labs Titanium joins 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.
6.150.1.2 SOUND SIGNATURES AT SHOOTER’S EAR
Real sound pressure histories from the same 6-shot test 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 shooter’s ear for all 6 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 Shots 1, 2, and 5. The real sound impulse (momentum transfer potential) histories at the ear from the same 6-shot test are shown in Figure 4. Full and short timescales are shown for Shots 1, 2, 4, and 5.
Figure 3a. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Ear Sound Pressure Signature
Figure 3b. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Ear Sound Pressure Signature, Short Time Window
Figure 4a. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Ear Sound Impulse Signature
Figure 4b. Otter Creek Labs Titanium Subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Ear Sound Impulse Signature
Much of the same behavior measured at the muzzle of the system is displayed in the waveforms measured at the shooter’s ear with the Otter Creek Labs Titanium. The signatures are of lower amplitude than that measured in the tests of both the Oculus and Jessie’s Girl, largely driven by more significant muzzle suppression. However, there are also other signature components contributing to less severity, including more normalized phase transitions and longer rise times. These differences are apparent upon primary momentum accumulation at approximately 32 ms (Figure 4) and carry over to maximum amplitude.
PEW Science Research Note 6: Ejection port blast load signature is still a driver of shooter’s risk with this system, but muzzle signature severity and timing pays dividends in reducing operator hazard, in totality, over the other conventional systems tested. It proves difficult to achieve a higher shooter’s ear Suppression Rating on this type of host weapon without the implementation of more advanced flow dynamics, as discussed in Research Note 4. FRP is effectively nullified to the shooter with the Otter Creek Labs Titanium on this host weapon, but the shooter’s ear Rating remains in the 70-zone, unable to reach the extreme hazard reduction of the CAT SR. Nonetheless, to iterate, the shooter’s ear suppression performance and overall hazard reduction of the Titanium is notable for any rimfire silencer, let alone a conventional design. It is highly optimized for this platform and PEW Science postulates the Titanium will perform well on a variety of short-barrel rimfire host weapons where backpressure is of limited concern to the operator.
PEW Science Research Note 7: It should be noted that the weight of the Otter Creek Labs Titanium is approximately 4 ounces. The short configuration of the Rugged Oculus weighs 4.3 ounces. For a similar weight, the performance of the Titanium on this host weapon is drastically higher; hazard to both the operator and bystanders has a differential of at least three Suppression Rating categories. Users may be unaware of the potential blast load signature hazards of short-barrel rimfire host weapons. Suppression of such systems is often non-trivial; subsonic rimfire cartridge combustion still produces blast loads that can subject both operators and bystanders to relatively high risk. For further context, with a shooter’s ear Suppression Rating of 47.1, the short configuration of the Rugged Oculus on the Beretta 21A produces a similar hazard to the weapon operator as a Abel Company Theorem-L on a 20-in .308 bolt-action rifle with supersonic ammunition (shooter’s ear Suppression Rating of 46.9). Whereas, the Otter Creek Labs Titanium possesses a shooter’s ear Suppression Rating of 73.0 on the Beretta 21A. This hazard is more similar to that of the operator shooting a Q Full Nelson on an 8-in subsonic 300 BLK bolt-action rifle. Suppressed small arm weapon system performance is a spectrum. The Suppression Rating is a universal damage risk criterion (DRC) metric and may be used to compare any system in the Rankings section of the Standard in free field hazard potential. It is not possible to use peak transient metrics alone, such as those reported in Table 1, to perform this type of hazard comparison. Peak transient metrics alone (peak pressure [dB] and impulse [dB-ms]) are inadequate for DRC applications and use of those types of metrics to predict personnel hazards may produce erroneous and potentially significantly unconservative results.
Further comparison of the Otter Creek Labs Titanium rimfire pistol suppression performance is provided below.
6.150.2 Suppression Rating Comparison - Semiautomatic Subsonic .22 LR
The Otter Creek Labs Titanium was developed to maximize pure sound signature reduction (PEW Science Suppression Rating) on high pressure rimfire hosts (e.g. semiautomatic pistols). Figure 6 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 6. Suppression Rating Comparisons Of Rimfire Silencers Using PEW-SOFT subsonic .22 LR Beretta 21A Subcompact Semiautomatic Pistol Test Data
The performance of the Otter Creek Labs Titanium on the short-barrel subcompact semiautomatic rimfire pistol platform is high. For a silencer with conventional baffle geometry, its total pressure field suppression performance is very high. The Titanium exhibits the 2nd highest overall sound field suppression performance on this host weapon system in the current dataset. Only the CAT SR exceeds its performance; the CAT SR being more advanced (see Research Note 4).
The high-pressure optimized baffle geometry of the Otter Creek Labs Titanium pays significant dividends in muzzle suppression performance, without significant compromise to operator hazard reduction. The performance gap between the Titanium and configurations like the short configuration of the Rugged Oculus are nontrivial; the two configurations have a differential of several categories on the Suppression Rating scale. With a high degree of FRP masking performance, light weight, and significant pistol suppression performance, the Titanium represents a significant performance benchmark for conventional rimfire silencers in the current state of practice.
The consistency of the Otter Creek Labs Titanium pays significant dividends in total pressure field suppression performance, as described in Section 6.150.1.2 of the Member article, allowing it to exceed the performance of the Resilient Suppressors Jessie’s Girl. The same consistency was noted in low-pressure bolt-action testing of the Titanium; a trait shared with that of the Rugged Oculus on that platform. The Titanium exceeds both the consistency and total suppression potential of the Oculus on this high-pressure pistol platform.
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 80-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.
6.150.3 Review Summary: Otter Creek Labs Titanium 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 Otter Creek Labs Titanium achieved a composite Suppression Rating™ of 82.8 in PEW Science testing.
The bolt-action rifle rimfire performance of the Otter Creek Labs Titanium is detailed in Sound Signature Review 6.149, in which it achieved a composite Suppression Rating of 91.4.
As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.
PEW Science Laboratory Staff Opinion:
The Otter Creek Labs Titanium is a lightweight rimfire silencer that exhibits competitive suppression performance on rifle systems with notable consistency. When used on shorter-barrel rimfire systems such as pistols, the performance of the Titanium is even more notable. The silencer is able to be disassembled for cleaning, possesses practical wrench-features, and is constructed entirely of titanium. For the size, weight, and performance envelope, the Otter Creek Labs Titanium demonstrates extremely competitive overall performance attributes in the current rimfire suppression state of practice.
An interesting consequence of the Titanium’s baffle design is high-pressure efficiency without significant compromise in low-pressure performance. Like the low-pressure-optimized Rugged Oculus, the Otter Creek Labs Titanium uses traditional baffle geometry with a curved cone component. However, the proportion of frontal baffle surface area and curvature in the Titanium is greater; this geometric change, coupled with it’s two notches and deeper overall throat and extra baffle, allow the Titanium to almost mimic the gas dynamics of the Oculus on a bolt-action rifle, while exceeding the performance of the Oculus on the shorter barrel high-pressure Beretta 21A. As high performance with low-pressure bolt-actions is relatively commonplace, a silencer design that is able to excel with higher pressures and still compete in the lower pressure regime is notable.
The measured FRP signature from the Titanium is relatively unique in that it does exhibit a high degree of severity masking on this host weapon platform. The Otter Creek Labs Titanium does produce measurable and noticeable FRP on a rimfire pistol, but just like it demonstrated on a bolt-action rifle, the FRP signature from the Titanium is postulated to exhibit only minimal severity differential relative to subsequent shots.
The consistency of the Otter Creek Labs Titanium pays significant dividends in total pressure field suppression performance, allowing it to exceed the performance of the Resilient Suppressors Jessie’s Girl. The same consistency was noted in low-pressure bolt-action testing of the Titanium; a trait shared with that of the Rugged Oculus on that platform. The Titanium exceeds both the consistency and total suppression potential of the Oculus on this high-pressure pistol platform.
For a silencer with conventional baffle geometry, the Titanium’s total pressure field suppression performance is very high. The Titanium exhibits the 2nd highest overall sound field suppression performance on this host weapon system in the current dataset. Only the CAT SR exceeds its performance; the CAT SR being more advanced.
The Otter Creek Labs Titanium silencer may be disassembled, therefore, it may be cleaned by brush, tumbler, or a variety of methods. Like monolithic titanium silencers, the Otter Creek Labs Titanium may also be cleaned with a variety of chemical solutions, without disassembly.
PEW Science has not evaluated the durability of the Otter Creek Labs Titanium, 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 Otter Creek Labs Titanium 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.
