SSS.8.1.21 - Suppressed AK Rifle Hazards - Resilient Suppressors Putnik Silencer Hazard Map Brief
/Resilient Suppressors Putnik on the Arsenal SAM7R and Arsenal SAM7C 7.62x39mm AK-Pattern Rifles with 16.3-in and 12.6-in Barrels - Hazard Maps
This Silencer Hazard Map Brief documents the free field blast overpressure hazards from the Resilient Suppressors Putnik fielded on the Arsenal SAM7R and Arsenal SAM7C 7.62x39mm AK-Pattern Rifles with 16.3-in and 12.6-in Barrels, respectively, firing Hornady American Gunner 123gr 7.62x39mm ammunition, as evaluated in technical Report 6.224 and as tabulated in record numbers 7.1.257 and 7.1.258 in the Rankings, respectively.
The average Suppression Rating hazard contours at 1.6 m silencer end cap elevation from the instrumented blast test of the Putnik silencer on the 16.3-in barrel system computed with the PEW-SOFT HD Blast Hazard Prediction Tool are shown in Figure 1. Hazard contours for the Putnik silencer on the 12.6-in barrel system are shown in Figure 2. The Suppression Rating hazard scale is shown in Figure 3. Ground-truth anchored Suppression Ratings from the technical reports are annotated 1.0 m left of the end cap (SR_muzzle) and 6 inches right of the shooter’s right ear (SR_ear) in both figures. Computational parameters and blast overpressure hazard field observations are provided below.
8.1.21.1 PEW-SOFT HD Computational Model Parameters
PEW-SOFT HD code Version 2.2.7 Alpha was used.
Contour elevation is 1.6 m above grade. No reflecting surfaces, other than the ground, are present in the model.
Grid resolution is 0.076 m (3 in).
The average semiautomatic jet stability index sigma_sa of the Putnik on the 16.3-in barrel system is 0.17. The Putnik silencer on the 12.6-in barrel system has a lower jet stability index of 0.14.
8.1.21.2 Resilient Suppressors Putnik Suppression Hazard Map Observations:
The Resilient Suppressors Putnik is an AK-platform optimized silencer with a high early-time flow rate and large expansion volume. Its distal vent array works in tandem with the aforementioned traits to produce lower system back pressure and lower frequency audible signature. The triaxial hybrid designs shares some features with the Jolene silencer but only in primary baffle geometry.
Hazard field differentials between the two tested AK systems are a function of system dwell time; the 16.3-in system has much more severe piston vent blast and ejection port blast than the 12.6-in system. This is shown in the hazard maps.
Interestingly, the 12.6-in system takes advantage of the high-pressure bias of the Putnik, resulting in a less hazardous forward field. Jet stability somewhat decreases due to the higher amplitude peak blast pressure, but gross severity decreases adjacent to the muzzle of the weapon system. This gives way to less hazards throughout the field.
The Putnik provides very consistent hazard fields after the first shot on both weapon systems. Blowdown momentum is significantly controlled.
fig 1. Otter Creek Labs OCM5 14.5-in M4A1 AR-15 Free Field Hazard Map Produced by PEW-SOFT HD Blast Hazard Prediction Tool using PEW Science Test Data
fig 2. Otter Creek Labs OCM6 14.5-in M4A1 AR-15 Free Field Hazard Map Produced by PEW-SOFT HD Blast Hazard Prediction Tool using PEW Science Test Data
Fig 3. PEW Science Suppression Rating Scale
