SSS.6.122 - Combat Application Technologies CAT/ODB/A1/718 and the Q mini FIX 300 BLK Subsonic
/Combat Application Technologies CAT/ODB/A1/718 on a Q mini FIX 300 BLK with 8-in Barrel
The CAT/ODB/A1/718 (“ODB” in this report) is designed by Combat Application Technologies (CAT). 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 1.6-inch diameter and the silencer core is 6.8 inches long, including its external flash hiding features. The silencer is HUB compatible (1.375”-24 tpi threading). Therefore, the user may install a variety of 3rd-party mounting systems and muzzle devices with the silencer. Length of the total system will vary, depending on mount choice. For example, use of the CAT/TSF X, a threaded coupler, will result in a total system length of 7.2 inches. However, with the CAT/SPOOKY1 flash hider installed into the CAT/TSF X, the total added length to the end of the flash hider is 5.3 inches. The entirety of the silencer is DMLS (3D-printed) from a proprietary Inconel alloy. The factory specified weight of the CAT/ODB/A1/718 Inconel core is 16.1 ounces. The CAT/ODB/A1 Titanium core model is also available, and weighs 8.7 ounces. Geometry is identical. The third-party muzzle brake used in testing resulted in a tested system length of approximately 7.5 inches. Both CAT/ODB/A1 models can be obtained from Combat Application Technologies.
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-CAT-059-001-23. Therefore, data pertaining to the CAT/ODB/A1/718 in this Sound Signature Review is published with the express written permission of Combat Application Technologies.
This Sound Signature Review contains single-test results using the ODB mounted with a 2-port muzzle brake to the Q mini FIX bolt action pistol, chambered in 300 BLK with an 8-inch barrel. Discreet Ballistics 190gr ammunition was used in the test.
- Section 6.122.1 contains the ODB test results and analysis.
- Section 6.122.2 contains Suppression Rating comparisons with selected .30 rifle silencers in the subsonic flow regime.
- Section 6.122.3 contains the review summary and PEW Science laboratory staff technical opinions.
Summary: When paired with the Q mini FIX 8” 300 BLK and fired with Discreet Ballistics 190gr Subsonic Target ammunition, the CAT/ODB/A1/718 achieved a composite Suppression Rating™ of 67.2 in PEW Science testing.
The supersonic 5.56 performance of the CAT/ODB/A1/718 is detailed in Sound Signature Review 6.120, in which it achieved a composite Suppression Rating of 36.7.
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
6.122.1 CAT/ODB/A1/718 Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the ODB 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. CAT/ODB/A1/718 Sound Metric Summary
6.122.1.1 SOUND SIGNATURES AT THE MUZZLE
Real sound pressure histories from a 5-shot test acquired with PEW-SOFT™ are shown below. 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 5 shots are shown in Figure 2a. A zoomed-in timescale displays the region of peak sound pressure in Figure 2b, for the first two shots. The real sound impulse (momentum transfer potential) histories from the same 5-shot test are shown in Figure 3. Again, full and short timescales are shown.
Fig 2a. CAT/ODB/A1/718 Bolt Action 300 BLK Muzzle Sound Pressure Signature
Fig 2b. CAT/ODB/A1/718 Bolt Action 300 BLK Muzzle Sound Pressure Signature, Short Time Window
Figure 3a. CAT/ODB/A1/718 Bolt Action 300 BLK Muzzle Sound Impulse Signature
Figure 3b. CAT/ODB/A1/718 Bolt Action 300 BLK Muzzle Sound Impulse Signature
The CAT/ODB/A1/718 exhibits unique behavior for a high flow rate silencer in the subsonic 300 BLK combustion regime. The combination of high sound suppression performance and its flow rate characteristics is unusual.
As was observed in the 5.56x45mm MK18 testing of the CAT ODB (6.120), the measured signatures in this subsonic 300 BLK test report also indicate atypical behavior. On the MK18, the ODB presents signature behavior that in some ways mirrors that of dedicated-bore 5.56mm silencers, while inducing weapon kinematic behavior common in the use of so-called Flow Through silencers.
The subsonic 300 BLK signatures, above, display relative consistency, repeatability, and an unusual first-round-pop (FRP) impulse accumulation profile. In 6.120.1.1, it was noted that the CAT ODB produces specific high level system behavior combining attributes of several silencers in the 5.56x45mm MK18 combustion regime. In the 8-in barrel subsonic 300 BLK combustion regime, the ODB signatures display the following attributes:
Consistent precursor waves are evident post-FRP (Fig. 1a) with an immediate FRP divergence.
FRP impulse accumulation is not nearly as significant as with traditional baffle silencers of similar muzzle Suppression Rating, and all impulse histories possess a shorter positive phase (Fig. 2a).
Impulse accumulation rate is significantly lower than in Flow Through silencers like the HUXWRX OSS HX-QD 762 (6.45) and the high flow rate SIG Sauer SLH300Ti (6.107).
The impulse waveforms exhibit a “smooth” consistency, with uniform amplitude during subsequent shots, post-FRP.
Alone, the above signature characteristics are notable, but not necessarily out of the ordinary for a high-performance silencer. However, in the subsonic 300 BLK regime, such signature behavior typically presents with longer blowdown. Furthermore, it is also typical for a high flow rate silencer to exhibit more erratic jetting and more expedient impulse accumulation. Because the CAT ODB does not present these behaviors, and because it influences weapon function like silencers such as the HUXWRX FLOW 762 Ti on the MK18 (6.114), PEW Science postulates that the so-called SURGE BYPASS technology in the CATB ODB functions favorably across combustion regimes, with regard to suppression performance. Preliminary postulations further indicate that SURGE BYPASS may be somewhat “pressure agnostic” in its behavior, in that the technology demonstrates efficacy over a wider envelope of pressure and duration than typical.
PEW Science Research Note 1: The above postulations are significant and are strongly supported by test data, analysis, and field evaluations. The reader is encouraged to examine the weapon kinematics measured in the MK18 data (6.120) in conjunction with the presented gas dynamics in that article. Traditionally, extremely high flow rate silencers contain few internal stages, and those stages consist of initial expedient proximal venting post-uncorking with later expedient distal venting post-array. The post-array behavior typically presents with extreme externally measured impulse rise-times due to velocity gradients from multi-path distal orifices directly fed by annular channels. In the case of the HUXWRX (OSS) HX-QD, these are overlapping toroidal paths. In the case of the SIG Sauer SLH300Ti, these are shorter annular paths with progressive interstitial baffle porting. The HX-QD Flow Through technology and SIG SLH technology vary primarily in path length, though the SLH technology does utilize more traditional baffles it its primary array. Both venting mechanisms are extremely similar and not necessarily complex in their implementations, other than in manufacturing method.
In SURGE BYPASS technology, there exist somewhat similar components to the above, with the primary differences being multi-stage flow geometry. The early time proximal venting is used in conjunction with advanced baffle arrays. Furthermore, distal venting exhibits a lack of direct annular coupling; this is one of the reasons why external gas momentum throttling is observed in both this test report (in the subsonic regime) and in 6.120 (supersonic 5.56x45mm).
PEW Science Research Note 2: The gas dynamics of SURGE BYPASS described in Research Note 1 are complex. In summary, the reader should note the following high-level conclusions within that previous context:
High flow rate silencers typically exhibit poor subsonic sound signature suppression, relative to more restrictive designs. The CAT ODB does not; it is an outlier. It performs more similarly to a Sig Sauer SRD762Ti-QD (6.39) and Diligent Defense Enticer L-Ti (6.88) in signature severity on this host than it does to high flow rate silencers.
The HUXWRX HX-QD 762 (6.45) and Sig Sauer SLH300Ti (6.107) are examples of high flow rate silencers. The CAT ODB bridges the gap between the technologies used in those two silencers and other staged designs. The SURGE BYPASS technology demonstrates efficacy in all regimes, and therefore may be considered more advanced. Increased efficacy of Flow Through technology in the subsonic regime over the HX-QD series with the HUXWRX FLOW series is currently unknown, pending future laboratory evaluation.
SURGE BYPASS technology, as demonstrated by the presented test data and analysis, allows a silencer to operate more efficiently than typical across combustion regimes, while reducing the propensity for weapon over function. Again, high subsonic suppression performance is unusual when combined with those traits.
PEW Science Research Note 3: The FRP at the muzzle from the ODB, in this regime, is noticeable to bystanders. A somewhat unique sound field produced by the silencer can result in masking of the severity to the operator. The full Member article contains more information on this phenomenon.
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.
With subsonic 300 BLK from an 8-inch barrel, the CAT/ODB/A1/718 produces a less severe signature to bystanders than many silencers on this host weapon. Direct comparisons with other silencers are provided in Section 6.122.2.
6.122.1.2 SOUND SIGNATURES AT SHOOTER’S EAR
Real sound pressure histories from the same 5-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 ear for all 5 shots are shown in Figure 4. 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. The real sound impulse (momentum transfer potential) histories at the ear from the same 5-shot test are shown in Figure 5. Full and short timescales are shown.
Figure 4a. CAT/ODB/A1/718 Bolt Action 300 BLK Ear Sound Pressure Signature
Figure 4b. CAT/ODB/A1/718 Bolt Action 300 BLK Ear Sound Pressure Signature, Short Time Window
Figure 5a. CAT/ODB/A1/718 Bolt Action 300 BLK Ear Sound Impulse Signature
Figure 5b. CAT/ODB/A1/718 Bolt Action 300 BLK Ear Sound Impulse Signature
Unusual characteristics in the CAT ODB subsonic 300 BLK signature persist at the shooter’s ear, just as they did at the muzzle. Atypical consistent negative phase dominating primary jetting is observed in pressure space, in Figure 4a, with a very unusual smoothing of the impulse accumulation from primary muzzle blast (Figure 5b).
PEW Science Research Note 4: The pressure and impulse amplitudes measured at the shooter’s ear in this test of the CAT ODB are not exceedingly low but the consistency of the gas dynamics and the uniformity of the flow pays dividends in not only favorable duration components of the signatures, but also in phase components. The lack of propensity for extreme “swings” in positive to negative pressure gradients result in the smooth impulse accumulation profiles observed in Figure 5. These consistent signatures, from shot to shot, coupled with a lack of sharp peaks, combine with the favorable duration components to produce a less severe signature to the operator. A future PEW Science Member Research Supplement will examine these signatures in further detail.
PEW Science Research Note 5: Another (perhaps serendipitous) consequence of the phenomenology discussed in Research Note 4 is the masking of FRP to the weapon operator. Whereas a bystander will find the FRP to be more noticeable with greater severity than subsequent shots, the shooter of this weapon system with a CAT ODB will find that the hearing damage risk potential during the first shot is on par with that of subsequent shots. This is somewhat unusual, but not without precedent. Sound field shape from suppressed small arms can be exceedingly complex due to gas velocity and jet shaping from the distal silencer orifice. This varying sound field, in conjunction with the impulse accumulation profile(s) noted above, are postulated by PEW Science to contribute to this phenomenon. The FRP impulse plateau after approximately 29.5 ms (Fig. 5b) is particularly noteworthy. It is largely unique in PEW Science laboratory testing in this regime, to date.
Overall, the signature to the shooter is on par with high performance subsonic 300 BLK silencers. The CAT ODB eclipsing the shooter’s ear Suppression Rating of the Sig Sauer SRD762Ti-QD is a significant performance conclusion, considering that the CAT ODB also allows early venting to facilitate less weapon over-function on reciprocating hosts. The performance combination, as previously described, is highly unusual. The SURGE BYPASS technology shows a high degree of efficacy.
Comparisons with other silencers in the subsonic flow regime are shown in Section 6.122.2, below.
6.122.2 Suppression Rating Comparison - Subsonic 300 BLK
The CAT/ODB/A1/718 was developed with a focus on various performance and signature reduction attributes, pure sound signature reduction (PEW Science Suppression Rating), and a high flow rate (low back pressure) for weapon function. As previously discussed, its subsonic sound signature suppression performance is highly unusual for its flow rate and other performance attributes. Figure 6 shows a performance comparison of many 30 caliber rifle silencer configurations tested with the subsonic 300 BLK cartridge shown in public PEW Science testing, to date. Unsuppressed and suppressed Suppression Ratings are shown for both the shooter and bystanders.
Figure 6. Suppression Rating Comparisons Of .30 Rifle Silencers Using PEW-SOFT 300 BLK Subsonic Test Data
As previously stated, the CAT/ODB/A1/718 exhibits unique behavior for a high flow rate silencer in the subsonic 300 BLK combustion regime. The combination of high sound suppression performance and its flow rate characteristics is unusual.
From the above data, it can be concluded that the CAT ODB exhibits higher overall suppression performance in the subsonic 300 BLK combustion regime than most silencers presented in the PEW Science dataset, to date. In fact, it is producing a shooter’s ear damage risk potential that is similar to that produced by the Sig Sauer SRD762Ti-QD (6.39). That comparison is notable, given the length of the two silencers, as well as their flow rates. Another notable comparison is the performance of the CAT ODB in this regime with that of the Diligent Defense Enticer L-Ti (6.88). The Enticer L series is also longer than the CAT ODB, and exhibits much more restrictive gas dynamics. The CAT/ODB/A1/718 also meets or exceeds the performance of the Surefire SOCOM300-SPS (6.57), which is a purpose-built 300 BLK silencer, and again, the ODB does it with high flow characteristics. The SOCOM300-SPS has significant back pressure.
As discussed in the PEW Science member version of this article, the sound field shape of the CAT ODB is unique. Like the aforementioned Enticer L-Ti, and the Silencer Central Banish 30 Gold (6.70), the muzzle and ear Suppression Ratings diverge. This type of divergence can occur for several reasons, including distal orifice flow shaping and overall flow rate, both of which influence gas velocity flow gradients. Typically, extremely high flow rate silencers also exhibit a larger divergence. The dataset above is consistent with this observation. Despite the divergence of the muzzle sound field and the lower muzzle Suppression Rating of the CAT ODB compared with some other high performance silencers, for example, the overall performance is still significant. For example, the ODB exhibits a higher overall muzzle Suppression Rating than the wiped configuration of the Energetic Armament VOX-S (6.38). For a high flow rate silencer to exceed that performance is unusual. The inner ear damage risk to the shooter from the CAT ODB, on this host, is not significantly different from that of the Otter Creek Labs Hydrogen-L (Review 6.94); a much longer silencer. This is also unusual, and significant in full context.
Given the length and flow rate of the CAT ODB, and the demonstrated efficacy of the SURGE BYPASS technology in the silencer, PEW Science considers this performance to be indicative of a significant advancement in the suppressed small arms state of practice.
The following items previously highlighted in Research Note 2 are worth mentioning again, here:
The HUXWRX HX-QD 762 (6.45) and Sig Sauer SLH300Ti (6.107) are examples of high flow rate silencers. The CAT ODB bridges the gap between the technologies used in those two silencers and other staged designs. The SURGE BYPASS technology demonstrates efficacy in all regimes, and therefore may be considered more advanced. Increased efficacy of Flow Through technology in the subsonic regime over the HX-QD series with the HUXWRX FLOW series is currently unknown, pending future laboratory evaluation.
SURGE BYPASS technology, as demonstrated by the presented test data and analysis, allows a silencer to operate more efficiently than typical across combustion regimes, while reducing the propensity for weapon over function. Again, high subsonic suppression performance is unusual when combined with those traits.
The difference in sound signature suppression performance from silencers in the subsonic 300 BLK suppression regime, is extremely significant. 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.
6.122.3 Review Summary: CAT/ODB/A1/718 on a Q mini FIX 300 BLK with 8-in Barrel
When paired with the Q mini FIX 8” 300 BLK and fired with Discreet Ballistics 190gr Subsonic Target ammunition, the CAT/ODB/A1/718 achieved a composite Suppression Rating™ of 67.2 in PEW Science testing.
The supersonic 5.56 performance of the CAT/ODB/A1/718 is detailed in previous Sound Signature Review 6.120, in which it achieved a composite Suppression Rating of 36.7.
As with all weapon systems, the user is encouraged to examine both muzzle and ear Suppression Ratings.
PEW Science Laboratory Staff Opinion:
The CAT/ODB/A1/718 (CAT ODB) is a relatively compact and extremely advanced 30 caliber machine gun rated rifle silencer that exhibits significant back pressure reduction and sound signature suppression performance, for its size and caliber designation. Its sound suppression performance on both subsonic 300 BLK and short barrel 5.56x45mm is significant. Notably, the CAT SURGE BYPASS technology in the silencer appears to balance high flow rate behavior with significant overall signature suppression, even when over-bored for the cartridge and even when using subsonic ammunition, which is highly unusual. The silencer is available in two 3D-printed material options; proprietary Inconel alloy and Titanium. The weights of both models are notable. The CAT ODB represents one of the most advanced systems evaluated by PEW Science, to date.
PEW Science postulates that the so-called SURGE BYPASS technology in the CATB ODB functions favorably across combustion regimes, with regard to suppression performance. Preliminary postulations further indicate that SURGE BYPASS may be somewhat “pressure agnostic” in its behavior, in that the technology demonstrates efficacy over a wider envelope of pressure and duration than typical. These postulations are significant and are strongly supported by test data, analysis, and field evaluations. The reader is encouraged to examine the weapon kinematics measured in the MK18 data (6.120) in conjunction with the presented gas dynamics in that article.
High flow rate silencers typically exhibit poor subsonic sound signature suppression, relative to more restrictive designs. The CAT ODB does not; it is an outlier. It performs more similarly to a Sig Sauer SRD762Ti-QD and Diligent Defense Enticer L-Ti in signature severity on this host than it does to high flow rate silencers. The HUXWRX HX-QD 762 and Sig Sauer SLH300Ti are examples of high flow rate silencers. The CAT ODB bridges the gap between the technologies used in those two silencers and other staged designs. The SURGE BYPASS technology demonstrates efficacy in all regimes, and therefore may be considered more advanced.
Given the length and flow rate of the CAT ODB, and the demonstrated efficacy of the SURGE BYPASS technology in the silencer, PEW Science considers this performance to be indicative of a significant advancement in the suppressed small arms state of practice.
The CAT ODB is offered with so-called HUB universal mount threading at the proximal end. It is not typical for high performance silencers with such technology to use non-proprietary mounts, because mount choice can sometimes significantly influence silencer and suppressed weapon system performance. One unique characteristic of the SURGE BYPASS technology in the CAT ODB is that the alpha parameter minimization is postulated to be robust with mount choice. In other words, different mounting schemes may not adversely influence SURGE BYPASS behavior as much as some other technologies such as Flow Through. Further laboratory evaluations are needed. The presented test data was acquired using a third-party 2-port muzzle brake, for reference.
The CAT ODB is available in both Inconel and Titanium versions. The Titanium version of the ODB has a core weight of only 8.7 ounces. The Inconel CAT/ODB/A1/718 has a core weight of 16.1 ounces. Users should note that, in general, the durability and sparking performance of Inconel vs. Titanium silencers may be significant. The PEW Science laboratory has evaluated the Inconel CAT/ODB/A1/718 in complete darkness on short barrel automatic centerfire rifles and semiautomatic 7.62mm rifles with visual, night vision, and thermal observation from the weapon operator. The signatures in all spectra are reduced when compared with identical weapon systems fielded with the HUXWRX FLOW 762 Ti, for example. This performance factor may be significant for some users.
In this review, the CAT/ODB/A1/718 performance metrics depend upon suppressing a subsonic intermediate rifle cartridge. While the sound signature of such cartridges can be suppressed to levels that may result in the desire of the shooter and bystanders to not wear hearing protection, PEW Science encourages the reader to remain vigilant with regard to all subsonic rifle cartridge suppression claims. The gas volume and combustion products created by firing a subsonic intermediate rifle cartridge such as 300 BLK are still significant; the measured pressure and impulse magnitudes, and their durations, illustrate this fact.
The hearing damage potential of subsonic rifle 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.
