SSS.6.1 - Rugged Oculus and the CZ452
/Rugged Suppressors Oculus on a CZ 452 American Bolt Action Rifle
The Oculus is manufactured by Rugged Suppressors. It is a 22 caliber rimfire silencer, intended to suppress .22LR, .22WMR, .17HMR, .17WSM, and 5.7x28mm. It has a 1.06-inch diameter and is modular, in that it can be configured in the user’s choice of two lengths. The length in the long configuration is 5.25 inches and the length in the short configuration is 3.25 inches. The silencer is constructed entirely of 17-4PH stainless steel (tube and baffles) and weighs 6.9 ounces or 4.3 ounces in the long or short configurations, respectively. The Oculus can be obtained from Silencer Shop.
This review contains single-test results using the Rugged Oculus on the CZ452 American Bolt Action rifle, chambered in .22LR with a 16-inch barrel. Results with both the long and short configurations of the Oculus on the CZ452 are shown with CCI Standard Velocity .22LR ammunition. PEW Science has performed multiple tests with the Oculus in both of its configurations with this host weapon and the Suppression Rating is an average of the rating from all tests.
PEW Science Errata: PEW-SOFT advancements have occurred since the original publication of this research. The Suppression Ratings at the shooter's ear have been updated in this article. The Composite Suppression Ratings in this article have also been updated, accordingly.
Summary: When paired with the CZ452 American bolt action rifle and fired with CCI SV .22LR ammunition in its long configuration, the Rugged Oculus has achieved an average Suppression Rating™ of 92.8 in PEW Science testing. In its short configuration with the same host weapon and ammunition, the Oculus has achieved an average Suppression Rating of 86.8.
6.1.1 Oculus Sound Signature Test Results (Long Configuration)
A summary of the principal Silencer Sound Standard performance metrics of the Oculus in its long configuration 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 0.15 m (6 in) right of the 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. Rugged Oculus (Long Configuration) Sound Metric Summary
6.1.1.1 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 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, here.
Figure 1 shows a 3-millisecond long sequence of events during the first test shot of the long configuration of the Oculus, as measured 1.0 m left of the muzzle. There are four significant events shown:
The firing pin drops to hit the primer, causing a 97.3 dB peak.
The next peak of 103.8 dB occurs as the primer compound ignites and the combustion products enter the chamber and barrel.
The bullet then exits the barrel muzzle, and the muzzle blast enters the silencer, resulting in a 104.1 dB peak.
Finally, the bullet and gas exit the silencer end-cap, and the 122.9 dB peak occurs.
This is the typical sequence observed when firing subsonic .22LR ammunition from a bolt-action rifle with an attached silencer.
Fig 1. Early-time Shot History, Rugged Oculus Full Configuration Bolt Action Rifle Muzzle Sound Pressure Signature, 10-AUG-2019
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. 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. Rugged Oculus Full Configuration Bolt Action Rifle Muzzle Sound Pressure Signature, 10-AUG-2019
Fig 2b. Rugged Oculus Full Configuration Bolt Action Rifle Muzzle Sound Pressure Signature, Small Time Window 10-AUG-2019
Figure 3a. Rugged Oculus Full Configuration Bolt Action Rifle Muzzle Sound Impulse Signature, 10-AUG-2019
Figure 3b. Rugged Oculus Full Configuration Bolt Action Rifle Muzzle Sound Impulse Signature, 10-AUG-2019
Figure 2 shows no sound pressure regime first-round-pop (FRP); shot 4 possesses the highest peak sound pressure (123 dB). Figure 3, however, shows a gradual decrease in peak positive-phase sound impulse from Shot 1 to Shot 5. PEW Science note: 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.
6.1.1.2 SOUND SIGNATURES AT SHOOTER’S EAR
Real sound pressure histories from a 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).
Figure 4 shows a 6-millisecond long sequence of events during the first test shot, as measured 0.15 m right of the shooter’s right ear. The same four significant events previously shown at the muzzle (Figure 1) are now shown from the perspective of the shooter’s ear:
The firing pin drops to hit the primer, causing a 107.4 dB peak.
The next peak of 111.2 dB occurs as the primer compound ignites and the combustion products enter the chamber and barrel.
The bullet then exits the barrel muzzle, and the muzzle blast enters the silencer, resulting in a 106.0 dB peak.
Finally, the bullet and gas exit the silencer end-cap, and the 118.4 dB peak occurs.
This is the typical sequence observed when firing subsonic .22LR ammunition from a bolt-action rifle with an attached silencer; note how the arrival times and pressure magnitudes differ depending on the measurement location (Figure 1 vs. Figure 4 - muzzle vs. ear).
Fig 4. Early-time Shot History, Rugged Oculus Full Configuration Bolt Action Rifle Ear Sound Pressure Signature, 10-AUG-2019
The primary sound signature pressure histories at the ear for all 5 shots are shown in Figure 5. 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 6. Again, full and short timescales are shown.
Figure 5a. Rugged Oculus Full Configuration Bolt Action Rifle Ear Sound Pressure Signature, 10-AUG-2019
Figure 5b. Rugged Oculus Full Configuration Bolt Action Rifle Ear Sound Pressure Signature, 10-AUG-2019
Figure 6a. Rugged Oculus Full Configuration Bolt Action Rifle Ear Sound Impulse Signature, 10-AUG-2019
Figure 6b. Rugged Oculus Full Configuration Bolt Action Rifle Ear Sound Impulse Signature, 10-AUG-2019
Figure 5 shows the highest peak at the shooter’s ear (the gas exiting the silencer) to occur much later in time that the sound of the firing pin, the powder-burn in the barrel, and the muzzle blast entering the silencer, as expected. Similar to the measurements at the muzzle, there is no FRP evident when examining the pressure histories at the shooter’s ear. However, there is also no FRP evident in the impulse histories at the shooter’s ear (Figure 6).
6.1.2 Oculus Sound Signature Test Results (Short Configuration)
A summary of the principal Silencer Sound Standard performance metrics of the Oculus in its short configuration is shown in Table 2. 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 0.15 m (6 in) right of the 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 2. Rugged Oculus (Short Configuration) Sound Metric Summary
6.1.2.1 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 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, here.
Figure 7 shows a 2.5-millisecond long sequence of events during the first test shot of the short configuration of the Oculus, as measured 1.0 m left of the muzzle. There are four significant events shown:
The firing pin drops to hit the primer, causing a 93.3 dB peak.
The next peak of 103.1 dB occurs as the primer compound ignites and the combustion products enter the chamber and barrel.
The bullet then exits the barrel muzzle, and the muzzle blast enters the silencer, eventually resulting in a 110.4 dB peak.
Finally, the bullet and gas exit the silencer end-cap, and the 120.5 dB peak is measured, followed by the maximum peak of 124.5 dB.
This sequence is similar to that observed with the long configuration of this silencer, albeit with some higher peaks and different timing due to the size of the silencer.
Fig 7. Early-time Shot History, Rugged Oculus Short Configuration Bolt Action Rifle Muzzle Sound Pressure Signature, 10-AUG-2019
The primary sound signature pressure histories for all 5 shots in the short configuration are shown in Figure 8a. A zoomed-in timescale displays the region of peak sound pressure in Figure 8b. The real sound impulse (momentum transfer potential) histories from the same 5-shot test are shown in Figure 9. Again, full and short timescales are shown.
Figure 8a. Rugged Oculus Short Configuration Bolt Action Rifle Muzzle Sound Pressure Signature, 10-AUG-2019
Figure 8b. Rugged Oculus Short Configuration Bolt Action Rifle Muzzle Sound Pressure Signature, Small Time Window, 10-AUG-2019
Figure 9a. Rugged Oculus Short Configuration Bolt Action Rifle Muzzle Sound Impulse Signature, 10-AUG-2019
Figure 9b. Rugged Oculus Short Configuration Bolt Action Rifle Muzzle Sound Impulse Signature, Short Time Window, 10-AUG-2019
As was shown in the tests of the long configuration, a view of the sound pressure regime in Figure 8 shows no FRP; this time, shot 5 possesses the highest peak sound pressure (130.4 dB). Figure 9, however, shows that the fastest rise to peak impulse does, in fact, occur in shot 1. Due to the difference in silencer volume and gas dynamics between the long and short configuration of the Oculus, FRP in the short configuration is evident only in early arrival time of peak sound impulse. Note that shot 3 in this configuration possesses the highest peak momentum transfer potential. PEW Science note: 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. In this case, the rise-time to peak impulse helps tell the story.
6.1.2.2 SOUND SIGNATURES AT SHOOTER’S EAR
Real sound pressure histories from a 5-shot test acquired with PEW-SOFT at the shooter’s ear are shown in Figure 7. 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 (energy) histories from the same 5-shot test are shown in Figure 8. Again, full and short timescales are shown.
Figure 10 shows a 6-millisecond long sequence of events during the first test shot of the short configuration, as measured 0.15 m right of the shooter’s right ear. The same four significant events previously shown at the muzzle (Figure 7) are now shown from the perspective of the shooter’s ear:
The firing pin drops to hit the primer, causing a 106.3 dB peak.
The next peak of 115.3 dB occurs as the primer compound ignites and the combustion products enter the chamber and barrel.
The bullet then exits the barrel muzzle, and the muzzle blast enters the silencer, resulting in a 109.6 dB peak.
Finally, the bullet and gas exit the silencer end-cap, and the 119.7 dB peak occurs.
This is, again, the typical sequence observed when firing subsonic .22LR ammunition from a bolt-action rifle with an attached silencer; note how the arrival times and pressure magnitudes differ depending on the measurement location (Figure 7 vs. Figure 10 - muzzle vs. ear and Figure 4 vs. Figure 10 - long vs. short configurations).
Fig 10. Early-time Shot History, Rugged Oculus Short Configuration Bolt Action Rifle Ear Sound Pressure Signature, 10-AUG-2019
The primary sound signature pressure histories at the ear for all 5 shots of the short configuration are shown in Figure 11. 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 12. Again, full and short timescales are shown.
Figure 11a. Rugged Oculus Short Configuration Bolt Action Rifle Ear Sound Pressure Signature, 10-AUG-2019
Figure 11b. Rugged Oculus Short Configuration Bolt Action Rifle Ear Sound Pressure Signature, Short Time Window, 10-AUG-2019
Figure 12a. Rugged Oculus Short Configuration Bolt Action Rifle Ear Sound Impulse Signature, 10-AUG-2019
Figure 12b. Rugged Oculus Short Configuration Bolt Action Rifle Ear Sound Impulse Signature, Short Time Window, 10-AUG-2019
Figure 11 shows the highest peak at the shooter’s ear (the gas exiting the silencer) to occur much later in time that the sound of the firing pin, the powder-burn in the barrel, and the muzzle blast entering the silencer, as expected (and was previously shown in Figure 5 for the long configuration). Similar to the measurements at the muzzle, there is no FRP evident when examining the pressure histories at the shooter’s ear. However, this time, FRP is clearly seen in the impulse regime at the shooter’s ear in Figure 12.
6.1.3 Review Summary: Rugged Oculus and the CZ452
When paired with the CZ452 American bolt action rifle and fired with CCI SV .22LR ammunition in its long configuration, the Rugged Oculus has achieved an average Suppression Rating of 92.8 in PEW Science testing. In its short configuration with the same host weapon and ammunition, the Oculus has achieved an average Suppression Rating of 86.8.
PEW Science Subjective Opinion:
The Rugged Oculus is a high performing rimfire silencer. The ability to configure the silencer differently based upon suppression and length preferences may be attractive to some users. The silencer is not the lightest on the market, but is extremely durable. With stainless steel baffles, cleaning of lead fouling may be accomplished with an ultrasonic cleaner or harsh solvents that may damage less resilient materials such as aluminum.
The sometimes advertised “no first round pop” of the Oculus does hold some factual value, in that the pressure regime often shows no discernible FRP, but Silencer Sound Standard metrics show otherwise. This should not be surprising, as the environmental differences of the silencer internal volume prior to the first shot and after the first shot will be different unless employing a novel gas-displacement apparatus to inject a material other than air into the silencer, or using some kind of ablative media.
