SSS.6.243 - JK Armament PRO-KOR 6 Mini and the MK18 10.3-in and M4 Mid-Gas 14.5-in Barrel 5.56x45mm Automatic AR15 Rifles (Free Version)
/JK Armament PRO-KOR 6 Mini on the 10.3-in MK18 and 14.5-in M4A1 5.56x45mm AR15 Rifles
The PRO-KOR 6 Mini Ti is designed and manufactured by JK Armament. It is a centerfire rifle silencer, optimized to suppress the 5.56x45mm NATO cartridge and is also compatible with .243 cartridges such as 6mm ARC. It has a 1.72-in diameter and is 4.6 inches long with no mount installed. The rear of the silencer is threaded 1.375-24tpi to accommodate “HUB” compatible mounting systems; the included War Eagle mount and coupler increases the total system length to 5.38 inches. The entirety of the silencer core is 3D-printed titanium. The HUB mount coupler is also titanium. The core of the silencer weighs 6.9 ounces and the 1/2-28tpi War Eagle mount and coupler weigh 4.4 ounces, for a total system weight of 11.3 ounces, as tested. The PRO-KOR 6 Mini Ti can be obtained from Silencer Shop.
System Suppression Ratings and Silencer Hazard Maps:
This report includes two (2) different tests of the JK Armament PRO-KOR 6 Mini Ti. Test data and analysis is presented with the silencer on both the 10.3-in MK18 and 14.5-in M4 short barrel rifles. Composite and Detailed Suppression Ratings, along with the predicted personnel hazards generated by the tested weapon systems in this report in the free field, are shown in the below graphics and Silencer Hazard Maps. Click or tap the Maps to enlarge. Please reference Silencer Hazard Map Brief 8.1.40 for further details. The PEW-SOFT HD Blast Hazard Prediction Tool and Hazard Mapper is presented in Report 8.1.1.
JK Armament PRO-KOR 6 Mini Ti 10.3-in MK18 AR-15 Free Field Hazard Map Produced by PEW-SOFT HD Blast Hazard Prediction Tool using PEW Science Test Data
JK Armament PRO-KOR 6 Mini Ti 14.5-in M4A1 AR-15 Free Field Hazard Map Produced by PEW-SOFT HD Blast Hazard Prediction Tool using PEW Science Test Data
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 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 analysis production for this Sound Signature Review was funded in part by PEW Science Project PEW-JK-140-002-26. Therefore, data pertaining to the PRO-KOR 6 Mini Ti in this Sound Signature Review is published with the express written permission of JK Armament.
The testing and analysis presented in this Sound Signature Review are of the JK Armament PRO-KOR 6 Mini Ti on both the 10.3-in MK18 Automatic AR-15 rifle and the 14.5-in M4A1 Mid-Gas Automatic AR-15 rifle, chambered in 5.56x45mm NATO. Federal XM193 55gr ammunition was used in the test.
The standard PEW Science MK18 test host weapon system is described in Public Research Supplement 6.51.
The standard PEW Science M4A1 test host weapon system is described in Public Research Supplement 6.127.
Report Table of Contents:
Section 6.243.1 contains an abbreviated overall summary of the JK Armament PRO-KOR 6 Mini Ti rifle silencer performance on both the 10.3-in MK18 and 14.5-in M4, compared with the Top 5 and Bottom 5 silencers in the current Rankings on both weapon systems.
Section 6.243.2 contains PRO-KOR 6 Mini Ti 10.3-in MK18 test results and analysis.
Section 6.243.3 contains PRO-KOR 6 Mini Ti 14.5-in M4A1 test results and analysis.
Section 6.243.4 contains overall Suppression Rating comparisons of the JK Armament PRO-KOR 6 Mini Ti silencer with other rifle silencers on the current market on both the 10.3-in MK18 and 14.5-in M4 rifles.
Section 6.243.5 contains an article summary and PEW Science laboratory staff opinions.
Summary:
When paired with the 10.3-in barrel MK18 and fired with M193, the JK Armament PRO-KOR 6 Mini Ti with the War Eagle mount achieved a Suppression Rating™ of 39.4 in PEW Science testing.
When paired with the 14.5-in barrel M4A1 and fired with M193, the JK Armament PRO-KOR 6 Mini Ti with the War Eagle mount achieved a Suppression Rating™ of 41.9 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.
6.243.1 JK Armament PRO-KOR 6 Mini Ti Silencer Automatic Rifle Suppression Performance Summary
The PEW Science Silencer Sound Standard includes the 5.56x45mm NATO evaluation of many rifle silencers. Comprehensive performance Rankings are tabulated in Section 7 of the Standard. This report examines the performance of the JK Armament PRO-KOR 6 Mini Ti silencer on both the standard untuned 10.3-in MK18 and 14.5-in M4A1 weapon systems.
Figure 1 presents a gross performance comparison of the JK Armament PRO-KOR 6 Mini Ti on the 10.3-in MK18 with the Top 5 and Bottom 5 performing silencers on that platform from the Rankings.
Figure 1. Suppression Rating Comparisons of JK Armament PRO-KOR 6 Mini Ti with the Top 5 and Bottom 5 5.56 Rifle Silencers Using PEW-SOFT 5.56x45mm Supersonic 10.3-in MK18 Test Data and PEW Science Analysis
Figure 2 presents a gross performance comparison of the JK Armament PRO-KOR 6 Mini Ti on the 14.5-in M4 with the Top 5 and Bottom 5 performing silencers on that platform from the Rankings.
Figure 2. Suppression Rating Comparisons of JK Armament PRO-KOR 6 Mini Ti with the Top 5 and Bottom 5 5.56 Rifle Silencers Using PEW-SOFT 5.56x45mm Supersonic 14.5-in M4A1 Test Data and PEW Science Analysis
Note that the JK Armament PRO-KOR 6 Mini Ti is not in the Top 5 of the Rankings for either weapon system, but is presented alongside the Top 5 and Bottom 5 silencers on each system for comparison.
The top five performing systems on the MK18 showcased in public evaluations are:
The bottom five performing systems on the MK18 showcased in public evaluations are:
The top five performing systems on the M4 showcased in public evaluations are:
The bottom five performing systems on the M4 showcased in public evaluations are:
The disparity between the suppression performance of the top 5 silencers and bottom five silencers on both the 10.3-in MK18 and 14.5-in M4 is mostly the result of technological advancement. In general, the top performers are hybrid designs. Of the bottom performers, the Surefire silencers and KAC silencers have hybrid design elements that pre-date the rest of the group. Surefire hybrid technology was derived from early OPS Inc. technology (see here). The CAT/TSWIF is also a hybrid design. However, being a blast diverter add-on with a truncated total length of 5 inches, it is at an inherent performance disadvantage when compared to the rest of the group.
The JK Armament PRO-KOR 6 Mini Ti is relatively short, with a total length including mount system of 5.4 inches. Also a hybrid design like its larger sister silencer the JK Armament PRO-KOR 556K (6.222), the suppression performance of the PRO-KOR 6 Mini Ti is highly competitive, regardless of barrel length. It should be noted that the PRO-KOR 6 Mini Ti is only somewhat outperformed by the larger K model on the MK18. The PRO-KOR 556K M4 evaluation is not yet published, but a similar relative comparison between the two silencers stands.
To be clear, it is not the addition of a single design element that produces high performance from a small arm weapon system silencer. It is the combination and purposefully engineered integration of multiple design elements that give way to high holistic system performance. Additive manufacturing is allowing for advanced designs to be implemented at scale; another benefit from additive manufacturing is rapid prototyping, enabling designers to iterate and optimize performance attributes of silencers more efficiently than they were able to do so in the past.
The above comparisons help to highlight several known phenomena and performance conclusions:
Silencer over-bore, in general, may reduce suppression performance but even dedicated bore silencers can underperform. In the bottom five silencers in the MK18 dataset shown in Figure 1, the over-bore silencers from both Surefire and Rugged found historical popular and industry-recommended use on 5.56 weapon systems. The Energetic Armament silencer was purposely over-bored in an effort to reduce baffle erosion under heavy firing schedules. In the partial M4 dataset shown in Figure 2, the bottom five performers all have a dedicated bore.
Rifle silencer suppression technology continues to advance at a rapid pace. The Stealth Additive Works, CAT SURGE BYPASS, PTR PIP, and other technologies are all extremely advanced. The JK Armament design that debuted in the PRO-KOR 556K and is implemented in the PRO-KOR 6 Mini Ti joins these technologies in the current state of the art in short barrel rifle suppression. In general, these systems are also optimized and produced with advanced manufacturing.
Operator protection on an untuned M4 almost always suffers without system tuning. The rifle is over-gassed, purposely by the manufacturer, for reliability purposes. This is the case with many stock AR-15 rifles. Even purposefully high flow rate silencers like the Spiritus 556i produce operator Suppression Rating metrics in the 20s on this standard host.
Operator protection is not necessarily correlated with “gas to the face” on an AR-15 system. Back pressure in a silencer, which is a function of internal early- and late-time flow rates, influences the severity of both ejection port blast and late-time gaseous byproducts of combustion from the chamber and gas tube, escaping from the ejection port of the rifle. Blowback can vary based on the rifle system, ammunition, firing schedule, and mounting system, even with the same silencer. In the case of the silencers in the above chart, all possess varying flow rates, and some provide less “gas to the face” than others, despite the operator (shooter’s ear) Suppression Ratings being somewhat similar on this standardized host rifle. Again, as stated in (3), the rifle is over-gassed, which reduces the resolution of ejection port blast correlation with back pressure. Nonetheless, as detailed in the raw shooter’s ear waveforms measured with silencers such as the Otter Creek Labs OCM5, severe back pressure signs are visible. These should be viewed as supplementary indicators in the analysis. The severe back pressure signs are not present in the raw blast test data of the BOE Mod 1, PTR VENT Spiritus, CAT ST, or Dillon DRC556, nor are they present in the raw blast data of the JK Armament PRO-KOR 6 Mini Ti.
The detailed 5.56x45mm NATO 10.3-in MK18 and 14.5-in M4A1 evaluations of the JK Armament PRO-KOR 6 Mini Ti rifle silencer follow.
6.243.2 JK Armament PRO-KOR 6 Mini Ti 10.3-in MK18 Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the JK Armament PRO-KOR 6 Mini Ti on the standard untuned MK18 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. JK Armament PRO-KOR 6 Mini Ti MK18 Sound Metric Summary
6.243.2.1 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, the fire control group positioned to single-shot, and the weapon was fired until the magazine was empty and the bolt locked back on the follower of the empty magazine. Only five shots are considered in the analysis. The signatures of Shot 6 are displayed in the data presentation but are not included in the analysis to maintain consistency with the overall PEW Science public dataset and bolt-closing signatures. 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 with the JK Armament PRO-KOR 6 Mini Ti are shown in Figure 3a. The sound signatures of Shot 1 and Shot 2 are shown in Figure 3b, in early time. The real sound impulse (momentum transfer potential) histories from the same 6-shot test are shown in Figure 4a. In Figure 4b, a shorter timescale is shown comparing the impulse of Shot 1 to that of Shots 2 and 3.
Fig 3a. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO MK18 Automatic Rifle Muzzle Sound Pressure Signature
Fig 3b. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO MK18 Automatic Rifle Sound Pressure Signature
Figure 4a. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO MK18 Automatic Rifle Muzzle Sound Impulse Signature
Figure 4b. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO MK18 Automatic Rifle Muzzle Sound Impulse Signature
Like the previously evaluated JK Armament PRO-KOR 556K (6.222), the PRO-KOR 6 Mini Ti is a relatively advanced hybrid design. The PRO-KOR 6 Mini Ti is approximately 0.8 inches shorter than the PRO-KOR 556K, which it achieves with a shorter first expansion (blast) chamber. The dual cavity baffle walls present in the longer K silencer are also present in the shorter Mini silencer for pressure staging. Also present is the same early blast chamber venting, spiral geometry flow shaping features on each baffle, and distal circumferential venting. The vented end cap is also similar between the two silencers, though it is removable from the larger K model but it is integrated to the 3D-print on the smaller Mini silencer.
In accordance with the above design similarities, the 3D-printed internal design features of the PRO-KOR 6 Mini Ti allow it to control blast momentum propagation to a significant degree when compared to many silencers previously evaluated on the MK18 weapon system. The risk field is forward-biased, away from the operator and adjacent bystanders, as illustrated in the Hazard Map at the beginning of this report and in Silencer Hazard Map Brief 8.1.40. Note that the suppression performance of the PRO-KOR 6 Mini Ti is only marginally lower than that of the PRO-KOR 556K. The back pressure is somewhat higher in the Mini silencer due to the only significant design difference being a smaller first expansion chamber. This is a somewhat unique case in modern silencer design and performance comparison in which only the blast chamber dimensions vary between two systems. Caution should be used when comparing blast chamber dimensions and drawing conclusions about back pressure; the two parameters seldomly scale directly between different designs.
PEW Science Research Note 1: The following observations are made from the above test data:
Relatively low free field blast overpressure amplitude through the entire time regime with somewhat faster bolt carrier group (BCG) return to battery than the K model (Fig. 3a).
Significant but controlled primary jetting followed by a relatively long duration blast momentum throttle (Fig. 3b and Fig. 4).
Consistency after first-round-pop (FRP) is high to moderate throughout blowdown with FRP momentum less throttled after peak accumulation than with the K model (Fig. 4b).
Interestingly, reducing the distance between the muzzle orifice to the first reflector (blast baffle) and decreasing the expansion volume in the blast chamber (forming the 6 Mini from the 556K) with the JK baffle design forces peak blast overpressure somewhat higher for a longer initial duration; this increases impulse accumulation as shown in Figure 3a. Observation (1) indicates back pressure may potentially increase as well. Observation (2) indicates the overall behavior from the two silencers is very similar, which stands to reason. Observation (3) seems to indicate a potential increase in FRP suppression efficiency with the Mini model.
PEW Science Research Note 2: Like the PRO-KOR 556K, a relatively unique feature of the PRO-KOR 6 Mini Ti is the baffle array layout. The pressure stages are composed of dual-wall baffle pairs with external and interstitial spiral ribbing. Gas expansion and surface area contact is varied progressively and repeatedly down the stack. The measured test data indicates that this design, along with the early venting, results in efficient performance for the length of the silencer even with a truncated blast chamber.
PEW Science Research Note 3: At the time of writing, the measured performance of the JK Armament PRO-KOR 6 Mini Ti places it right outside the top 10 of the overall MK18 PEW Science Rankings, slightly above the Maxim Defense DSX (6.110) and Otter Creek Labs Partially Vented End Cap Infinity 556K (6.233). As tested, the DSX is significantly (2.5-in) longer than the PRO-KOR 6 Mini Ti and the Infinity 556K is 0.75-in longer than the 6 Mini Ti. The JK Armament silencer has relatively balanced performance; its elevated muzzle (bystander) Suppression Rating further differentiates it from several silencers, elevating its Composite Suppression Rating. For further context regarding both performance and size balance, the reader is encouraged to use the Suppression Rating Parametric Visualization Tool (Members Only) for independent study.
PEW Science Research Note 4: It is extremely important for the reader to understand the Suppression Ratings are computed with free field test data, and are therefore universal when translating the weapon and operator to different environments without reflections. However, when the environment becomes complex with many reflecting surfaces, performance translation of different systems is not yet possible; sound field shapes and particle velocities result in varied blast wave time-of-arrivals, as well as changes of blast load angles of incidence; these variations change amplitude and phase waveform components. As a result of these inevitable environmental complexities, user impressions will vary, as both the shooter and bystander. Nonetheless, hazard reduction efficacy in the free field, as characterized by the Suppression Rating, holds. The Suppression Rating comparisons are the current state-of-the-art, and the most “apples to apples” sound suppression performance comparisons that currently exist. Further research is ongoing.
PEW Science Research Note 5: As in all semiautomatic AR15 weapon testing, a second pressure pulse originates from the ejection-port signature of the weapon and it occurs early enough in time such that its waves coalesce with that of the muzzle signature. However, in late time (at approximately 82 ms in Figure 3a) the mechanical noise of the bolt closing is observed. The pressure signature of Shot 6 does not display this event due to the bolt remaining open after the sixth and final round is fired from the magazine.
PEW Science Research Note 6: The closing time of the AR15 bolt is directly related to the flow restriction of a silencer for a given weapon system. PEW Science has determined bolt closing time variation from the unsuppressed state to be a reliable indicator of silencer back pressure, with strong correlation with the PEW Science Back Pressure Metric, Omega and the alpha parameter. However, PEW Science has also determined that the indicator may be unreliable upon upper receiver fouling. Sound signatures are not influenced by this fouling, as these kinematics occur in late time, after gas venting to atmosphere. Momentum transfer, weapon condition (upper receiver fouling), and other factors, can significantly influence bolt closing time. PEW Science urges the reader to exercise extreme caution if using the published bolt closing time to make determinations regarding silencer flow restriction (back pressure) or weapon system kinematics. This type of calculation may provide erroneous results, as the weapon condition at the time of each test is not published data. The time-scale duration showing bolt closing time is only published by PEW Science such that the signature data pedigree may be verified. The entire signatures are used in analysis and Suppression Rating calculations.
The shape, timing, and magnitudes of the early-time pressure pulses and overall shape of the impulse waveforms measured at the muzzle, from shot-to-shot, are relatively consistent. The consistency of the waveform amplitudes highlight the silencer’s overall sound performance consistency at the muzzle after the FRP, as well as the relative consistency of the tested automatic rifle firearm configuration.
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 Research Note 7: Note that the muzzle Suppression Rating of the JK Armament PRO-KOR 6 Mini Ti is 39.1 and the at-ear Suppression Rating is 25.5; different zones on the Suppression Rating Dose Chart, but both higher than typical on this weapon system. The somewhat lower back pressure of the PRO-KOR 6 Mini Ti, along with its strong muzzle suppression, contributes to a less severe ejection port blast signature, which further decreases shooter hazard on the standard MK18 weapon system. The reader is encouraged to examine the Silencer Hazard Map at the top of this report as detailed in Silencer Hazard Map Brief 8.1.40. Weapon tuning will influence hazard reduction efficacy, and is outside the scope of this study.
The signatures measured at the shooter’s ear with the PRO-KOR 6 Mini Ti on the MK18 are presented and examined in the full Member Version of this report.
This concludes the 10.3-in MK18 evaluation of the silencer. The 14.5-in M4 evaluation follows.
6.243.3 JK Armament PRO-KOR 6 Mini Ti 14.5-in M4 Sound Signature Test Results
A summary of the principal Silencer Sound Standard performance metrics of the JK Armament PRO-KOR 6 Mini Ti on the standard untuned M4 is shown in Table 2. 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 2. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO M4A1 Sound Metric Summary
6.243.3.1 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, the fire control group positioned to single-shot, and the weapon was fired until the magazine was empty and the bolt locked back on the follower of the empty magazine. Only five shots are considered in the analysis. The signatures of Shot 6 are displayed in the data presentation but are not included in the analysis to maintain consistency with the overall PEW Science public dataset and bolt-closing signatures. 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 with the JK Armament PRO-KOR 6 Mini Ti are shown in Figure 7a. The sound signatures of Shot 1 and Shot 2 are shown in Figure 7b, in early time. The real sound impulse (momentum transfer potential) histories from the same 6-shot test are shown in Figure 8a. In Figure 8b, a shorter timescale is shown comparing the impulse of Shot 1 to that of Shots 2 and 3.
Fig 7a. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO M4A1 Automatic Rifle Muzzle Sound Pressure Signature
Fig 7b. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO M4A1 Automatic Rifle Muzzle Sound Pressure Signature, short time window
Fig 8a. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO M4A1 Automatic Rifle Muzzle Sound Impulse Signature
Fig 8b. JK Armament PRO-KOR 6 Mini Ti 5.56x45mm NATO M4A1 Automatic Rifle Muzzle Sound Impulse Signature, short time window
On the 14.5-in mid-length gas M4, the performance of the PRO-KOR 6 Mini Ti is somewhat similar to its performance on the 10.3-in standard MK18. However, the approximately 40 percent longer barrel reduces peak blast pressure amplitude into the silencer and also increases projectile velocity. The PRO-KOR technology shows relatively strong performance scaling between the two weapon systems, though there are some distinct signature differences:
Lower peak blast overpressure and blast impulse (Fig. 7a).
Shorter positive phase duration of the first coupled jet (Fig. 7b).
Somewhat faster decay of latent jetting (Fig. 7b).
More significant FRP divergence (Fig. 8b).
Somewhat less relative stability during Shot 2 (Fig. 8b).
PEW Science Research Note 11: Observations (1), (2), and (3) are a function of the lower input pressure into the silencer. Observations (4) and (5) point to a potential high-pressure bias with the technology which is not necessarily a negative performance trait. The raw blast data from the two tests in this report, along with the calculated Suppression Rating metrics at the muzzle and ear, indicate that the PRO-KOR 6 Mini Ti does exhibit increased performance with longer barrels. However, the data and analysis also indicates that performance does not significantly drop with short barrels. For such a short silencer to reach a Suppression Rating of almost 40 at the 1.0 meter left of muzzle location is significantly notable and the JK Armament silencer does this on the 10.3-in barrel MK18. On the 14.5-in barrel M4, it exceeds that benchmark.
At the time of writing, the measured performance of the JK Armament PRO-KOR 6 Mini Ti places it inside the top 10 of the overall M4 PEW Science Rankings.
The signatures measured at the shooter’s ear with the PRO-KOR 6 Mini Ti on the 14.5-in M4 are presented and examined in the full Member Version of this report.
Comparison with the rest of the silencers in MK18 and M4 Rankings follows.
6.243.4 Suppression Rating Comparison (5.56x45mm from the MK18 and M4A1)
Presented below is a comparison of the PEW Science Suppression Ratings of the JK Armament PRO-KOR 6 Mini Ti rifle silencer with those of several other silencers on the MK18 and M4A1 weapon systems, respectively. The standard PEW Science MK18 test host weapon system is described in Public Research Supplement 6.51. The standard PEW Science M4A1 test host weapon system is described in Public Research Supplement 6.127.
Figure 11 presents an overall summary of the postulated hazards to the operator and bystanders when fielding a variety of different silencers on the standard MK18 weapon system. The JK Armament PRO-KOR 6 Mini Ti from this test program is shown in red.
Figure 12 presents an overall summary of the postulated hazards to the operator and bystanders when fielding a variety of different silencers on the standard M4 weapon system. Again, the JK Armament PRO-KOR 6 Mini Ti from this test program is shown in red.
Figure 11. Suppression Rating Comparisons of JK Armament PRO-KOR 6 Mini Ti with other Rifle Silencers Using PEW-SOFT 5.56x45mm Supersonic 10.3-in MK18 Test Data and PEW Science Analysis
Figure 12. Suppression Rating Comparisons of JK Armament PRO-KOR 6 Mini Ti with other Rifle Silencers Using PEW-SOFT 5.56x45mm Supersonic 14.5-in M4A1 Test Data and PEW Science Analysis
Hazards in the above figures are expressed with the Suppression Rating; a holistic parameter that captures human inner ear damage risk potential from a measured impulsive complex overpressure signature during the entire time regime of weapon operation, including combustion, complete blowdown, and all mechanical operation, including the carrier group returning to battery, in the true free field. The parameter may be used with the dose chart at the beginning of this report. The PEW Science Suppression Rating is a damage risk criterion (DRC), a lower Suppression Rating indicates a higher personnel hazard in the free field - it is not a subjective quantity; it is an objective quantification of hearing damage risk potential. Due to its true free field test data origin and complete waveform analytical calculation basis, it is the only known universal suppressed weapon system signature comparison metric available. Analytically computed metrics are color-coded in the Rankings Table, in all Silencer Hazard Maps, and keyed to the dose chart for user interpretation.
The following gross conclusions can be made from the metrics presented above:
The JK Armament PRO-KOR 6 Mini Ti produces free field bystander hazard reduction on par with the following silencers on the 10.3-in MK18 weapon system:
The MK18 operator protection with the PRO-KOR 6 Mini Ti is on par with or exceeding that of the:
The JK Armament PRO-KOR 6 Mini Ti produces free field bystander hazard reduction on par with the following silencers on the 14.5-in M4 weapon system:
The M4 operator protection with the PRO-KOR 6 Mini Ti is on par with or exceeding that of the:
PEW Science Research Note 13: Without weapon system tuning, operator hazards from a suppressed MK18, in the free field, plateau at Suppression Ratings near 30. Operator hazards from a suppressed M4 are even higher due to even more severe ejection port blast loads. Silencers with similar shooter’s ear Suppression Ratings will not sound the same to the shooter, in the free field. On the contrary, what an operator hears through the entire time regime of a gun shot event and subsequent environmental reflections, and which acute hazards manifest, may be different. The reader is strongly encouraged to review the published Silencer Hazard Map at the top of this report and in Silencer Hazard Map Brief 8.1.40. Furthermore, to illustrate two extremes, the difference in spatial hazards from a Flow Through silencer and a high back pressure silencer are directly compared in Silencer Hazard Map Brief 8.1.5 (HUXWRX FLOW 556k vs. SilencerCo Saker 556).
PEW Science Research Note 14: The JK Armament PRO-KOR 6 Mini Ti falls right outside the top 10 MK18 and inside the top 10 M4 PEW Science Rankings, as of the date of this report publication. The silencer is only 4.6 inches long without a mount, and 5.38-in long, as tested. This is therefore a significant performance achievement. Hybrid designs continue to demonstrate significant performance with supersonic ammunition suppression, and silencers like the PRO-KOR series, and others, show that performance can be achieved in compact design envelopes. The performance of these next generation systems are significantly elevated when compared to that of highly prolific previous generation hybrids such as the Surefire SOCOM556-RC2 (6.52) and other newly released military silencer hybrids such as the KAC PRT family (6.156) on this weapon system. Users now have additional high performance practical options to reduce weapon system length and maintain hazard reduction.
As detailed in this report, signature at the operator’s head is a function of both muzzle and ejection port signatures from the AR-15 weapon system. Specific weapon system parameters will dictate modification efficacy.
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.
6.243.5 Review Summary: JK Armament PRO-KOR 6 Mini on the 10.3-in MK18 and 14.5-in M4A1 5.56x45mm AR15 Rifles
When paired with the 10.3-in barrel MK18 and fired with M193, the JK Armament PRO-KOR 6 Mini Ti with the War Eagle mount achieved a Suppression Rating™ of 39.4 in PEW Science testing.
When paired with the 14.5-in barrel M4A1 and fired with M193, the JK Armament PRO-KOR 6 Mini Ti with the War Eagle mount achieved a Suppression Rating of 41.9 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 JK Armament PRO-KOR 6 Mini Ti is a compact 5.56 rifle silencer with competitive suppression performance and a balanced flow rate. The silencer is printed from titanium alloy and like the larger PRO-KOR 556K, it uses advanced hybrid geometry to achieve efficient blast propagation control for its size. Blast hazard is projected forward, away from the operator. The silencer is HUB-mount compatible. The silencers in the PRO-KOR series are significantly different from previous modular JK Armament silencer designs and present an example of the rapid advancement of rifle silencer suppression technology.
Like the previously evaluated JK Armament PRO-KOR 556K, the PRO-KOR 6 Mini Ti is a relatively advanced hybrid design. The PRO-KOR 6 Mini Ti is approximately 0.8 inches shorter than the PRO-KOR 556K, which it achieves with a shorter first expansion (blast) chamber. The dual cavity baffle walls present in the longer K silencer are also present in the shorter Mini silencer for pressure staging. Also present is the same early blast chamber venting, spiral geometry flow shaping features on each baffle, and distal circumferential venting. The vented end cap is also similar between the two silencers, though it is removable from the larger K model but it is integrated to the 3D-print on the smaller Mini silencer.
At the time of writing, the measured performance of the JK Armament PRO-KOR 6 Mini Ti places it right outside the top 10 of the overall MK18 PEW Science Rankings, slightly above the Maxim Defense DSX and Otter Creek Labs Partially Vented End Cap Infinity 556K. As tested, the DSX is significantly (2.5-in) longer than the PRO-KOR 6 Mini Ti and the Infinity 556K is 0.75-in longer than the 6 Mini Ti. The JK Armament silencer has relatively balanced performance; its elevated muzzle (bystander) Suppression Rating further differentiates it from several silencers, elevating its Composite Suppression Rating. For further context regarding both performance and size balance, the reader is encouraged to use the Suppression Rating Parametric Visualization Tool (Members Only) for independent study. The measured performance of the JK Armament PRO-KOR 6 Mini Ti places it inside the top 10 of the overall M4 PEW Science Rankings.
The PRO-KOR 6 Mini Ti is only 4.6 inches long without a mount. The tested War Eagle flash hider / compensator muzzle device and mount coupler induced extra system length. It is possible that using a shorter direct-thread mount may influence system performance, but the amount of performance change is unknown.
Unlike the Haynes nickel-chromium-cobalt alloy construction of the PRO-KOR 556K, the PRO-KOR 6 Mini Ti is constructed from titanium. Durability may differ depending on firing schedule. PEW Science has not evaluated the durability of this silencer. As always, the user should remain cognizant of their personal firing schedules. The user should contact JK Armament to ensure compatibility for their use case.
In this review, the JK Armament PRO-KOR 6 Mini Ti performance metrics depend upon suppressing a supersonic centerfire rifle cartridge on a short barrel gas-operated rifle, which is an incredibly difficult 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 5.56x45mm cartridge are significant; the measured pressure and impulse magnitudes, and their durations, illustrate this fact. Silencer performance on automatic (reciprocating) rifles depends on many factors. Weapon configuration may significantly influence total suppressed small arm system performance.
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.
